ETH Price: $2,123.14 (-0.84%)

Transaction Decoder

Block:
24693838 at Mar-19-2026 08:10:35 PM +UTC
Transaction Fee:
0.000004629566147 ETH $0.009829
Gas Used:
61,060 Gas / 0.07581995 Gwei

Emitted Events:

500 FiatTokenProxy.0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef( 0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef, 0x0000000000000000000000005c12c2b8c38967a7373ca0a3384831e2d02395eb, 0x000000000000000000000000d25cbfebbaa009ff19ec5c4233a1f5eaa553b703, 0000000000000000000000000000000000000000000000000000000005cea12a )

Account State Difference:

  Address   Before After State Difference Code
0.072320276711447631 Eth0.072320627806447631 Eth0.000000351095
0x578f5338...F172EE292
2.635630858733298709 Eth
Nonce: 295243
2.635626229167151709 Eth
Nonce: 295244
0.000004629566147
0xA0b86991...E3606eB48

Execution Trace

WalletSimple.flushForwarderTokens( forwarderAddress=0x5C12C2b8C38967a7373CA0A3384831E2d02395eb, tokenContractAddress=0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48 )
  • WalletSimple.flushForwarderTokens( forwarderAddress=0x5C12C2b8C38967a7373CA0A3384831E2d02395eb, tokenContractAddress=0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48 )
    • 0x5c12c2b8c38967a7373ca0a3384831e2d02395eb.3ef13367( )
      • Forwarder.flushTokens( tokenContractAddress=0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48 )
        • FiatTokenProxy.70a08231( )
          • FiatTokenV2_2.balanceOf( account=0x5C12C2b8C38967a7373CA0A3384831E2d02395eb ) => ( 97427754 )
          • FiatTokenProxy.a9059cbb( )
            • FiatTokenV2_2.transfer( to=0xD25CBfebbAA009fF19EC5C4233A1F5EAa553b703, value=97427754 ) => ( True )
              flushForwarderTokens[WalletSimple (ln:306)]
              File 1 of 5: WalletSimple
              // SPDX-License-Identifier: Apache-2.0
              pragma solidity 0.8.10;
              import './TransferHelper.sol';
              import './ERC20Interface.sol';
              import './IForwarder.sol';
              /** ERC721, ERC1155 imports */
              import '@openzeppelin/contracts/token/ERC721/IERC721Receiver.sol';
              import '@openzeppelin/contracts/token/ERC1155/utils/ERC1155Receiver.sol';
              /**
               *
               * WalletSimple
               * ============
               *
               * Basic multi-signer wallet designed for use in a co-signing environment where 2 signatures are required to move funds.
               * Typically used in a 2-of-3 signing configuration. Uses ecrecover to allow for 2 signatures in a single transaction.
               *
               * The first signature is created on the operation hash (see Data Formats) and passed to sendMultiSig/sendMultiSigToken
               * The signer is determined by verifyMultiSig().
               *
               * The second signature is created by the submitter of the transaction and determined by msg.signer.
               *
               * Data Formats
               * ============
               *
               * The signature is created with ethereumjs-util.ecsign(operationHash).
               * Like the eth_sign RPC call, it packs the values as a 65-byte array of [r, s, v].
               * Unlike eth_sign, the message is not prefixed.
               *
               * The operationHash the result of keccak256(prefix, toAddress, value, data, expireTime).
               * For ether transactions, `prefix` is "ETHER".
               * For token transaction, `prefix` is "ERC20" and `data` is the tokenContractAddress.
               *
               *
               */
              contract WalletSimple is IERC721Receiver, ERC1155Receiver {
                // Events
                event Deposited(address from, uint256 value, bytes data);
                event SafeModeActivated(address msgSender);
                event Transacted(
                  address msgSender, // Address of the sender of the message initiating the transaction
                  address otherSigner, // Address of the signer (second signature) used to initiate the transaction
                  bytes32 operation, // Operation hash (see Data Formats)
                  address toAddress, // The address the transaction was sent to
                  uint256 value, // Amount of Wei sent to the address
                  bytes data // Data sent when invoking the transaction
                );
                event BatchTransfer(address sender, address recipient, uint256 value);
                // this event shows the other signer and the operation hash that they signed
                // specific batch transfer events are emitted in Batcher
                event BatchTransacted(
                  address msgSender, // Address of the sender of the message initiating the transaction
                  address otherSigner, // Address of the signer (second signature) used to initiate the transaction
                  bytes32 operation // Operation hash (see Data Formats)
                );
                // Public fields
                mapping(address => bool) public signers; // The addresses that can co-sign transactions on the wallet
                bool public safeMode = false; // When active, wallet may only send to signer addresses
                bool public initialized = false; // True if the contract has been initialized
                // Internal fields
                uint256 private constant MAX_SEQUENCE_ID_INCREASE = 10000;
                uint256 constant SEQUENCE_ID_WINDOW_SIZE = 10;
                uint256[SEQUENCE_ID_WINDOW_SIZE] recentSequenceIds;
                /**
                 * Set up a simple multi-sig wallet by specifying the signers allowed to be used on this wallet.
                 * 2 signers will be required to send a transaction from this wallet.
                 * Note: The sender is NOT automatically added to the list of signers.
                 * Signers CANNOT be changed once they are set
                 *
                 * @param allowedSigners An array of signers on the wallet
                 */
                function init(address[] calldata allowedSigners) external onlyUninitialized {
                  require(allowedSigners.length == 3, 'Invalid number of signers');
                  for (uint8 i = 0; i < allowedSigners.length; i++) {
                    require(allowedSigners[i] != address(0), 'Invalid signer');
                    signers[allowedSigners[i]] = true;
                  }
                  initialized = true;
                }
                /**
                 * Get the network identifier that signers must sign over
                 * This provides protection signatures being replayed on other chains
                 * This must be a virtual function because chain-specific contracts will need
                 *    to override with their own network ids. It also can't be a field
                 *    to allow this contract to be used by proxy with delegatecall, which will
                 *    not pick up on state variables
                 */
                function getNetworkId() internal virtual pure returns (string memory) {
                  return 'ETHER';
                }
                /**
                 * Get the network identifier that signers must sign over for token transfers
                 * This provides protection signatures being replayed on other chains
                 * This must be a virtual function because chain-specific contracts will need
                 *    to override with their own network ids. It also can't be a field
                 *    to allow this contract to be used by proxy with delegatecall, which will
                 *    not pick up on state variables
                 */
                function getTokenNetworkId() internal virtual pure returns (string memory) {
                  return 'ERC20';
                }
                /**
                 * Get the network identifier that signers must sign over for batch transfers
                 * This provides protection signatures being replayed on other chains
                 * This must be a virtual function because chain-specific contracts will need
                 *    to override with their own network ids. It also can't be a field
                 *    to allow this contract to be used by proxy with delegatecall, which will
                 *    not pick up on state variables
                 */
                function getBatchNetworkId() internal virtual pure returns (string memory) {
                  return 'ETHER-Batch';
                }
                /**
                 * Determine if an address is a signer on this wallet
                 * @param signer address to check
                 * returns boolean indicating whether address is signer or not
                 */
                function isSigner(address signer) public view returns (bool) {
                  return signers[signer];
                }
                /**
                 * Modifier that will execute internal code block only if the sender is an authorized signer on this wallet
                 */
                modifier onlySigner {
                  require(isSigner(msg.sender), 'Non-signer in onlySigner method');
                  _;
                }
                /**
                 * Modifier that will execute internal code block only if the contract has not been initialized yet
                 */
                modifier onlyUninitialized {
                  require(!initialized, 'Contract already initialized');
                  _;
                }
                /**
                 * Gets called when a transaction is received with data that does not match any other method
                 */
                fallback() external payable {
                  if (msg.value > 0) {
                    // Fire deposited event if we are receiving funds
                    emit Deposited(msg.sender, msg.value, msg.data);
                  }
                }
                /**
                 * Gets called when a transaction is received with ether and no data
                 */
                receive() external payable {
                  if (msg.value > 0) {
                    // Fire deposited event if we are receiving funds
                    // message data is always empty for receive. If there is data it is sent to fallback function.
                    emit Deposited(msg.sender, msg.value, '');
                  }
                }
                /**
                 * Execute a multi-signature transaction from this wallet using 2 signers: one from msg.sender and the other from ecrecover.
                 * Sequence IDs are numbers starting from 1. They are used to prevent replay attacks and may not be repeated.
                 *
                 * @param toAddress the destination address to send an outgoing transaction
                 * @param value the amount in Wei to be sent
                 * @param data the data to send to the toAddress when invoking the transaction
                 * @param expireTime the number of seconds since 1970 for which this transaction is valid
                 * @param sequenceId the unique sequence id obtainable from getNextSequenceId
                 * @param signature see Data Formats
                 */
                function sendMultiSig(
                  address toAddress,
                  uint256 value,
                  bytes calldata data,
                  uint256 expireTime,
                  uint256 sequenceId,
                  bytes calldata signature
                ) external onlySigner {
                  // Verify the other signer
                  bytes32 operationHash = keccak256(
                    abi.encodePacked(
                      getNetworkId(),
                      toAddress,
                      value,
                      data,
                      expireTime,
                      sequenceId
                    )
                  );
                  address otherSigner = verifyMultiSig(
                    toAddress,
                    operationHash,
                    signature,
                    expireTime,
                    sequenceId
                  );
                  // Success, send the transaction
                  (bool success, ) = toAddress.call{ value: value }(data);
                  require(success, 'Call execution failed');
                  emit Transacted(
                    msg.sender,
                    otherSigner,
                    operationHash,
                    toAddress,
                    value,
                    data
                  );
                }
                /**
                 * Execute a batched multi-signature transaction from this wallet using 2 signers: one from msg.sender and the other from ecrecover.
                 * Sequence IDs are numbers starting from 1. They are used to prevent replay attacks and may not be repeated.
                 * The recipients and values to send are encoded in two arrays, where for index i, recipients[i] will be sent values[i].
                 *
                 * @param recipients The list of recipients to send to
                 * @param values The list of values to send to
                 * @param expireTime the number of seconds since 1970 for which this transaction is valid
                 * @param sequenceId the unique sequence id obtainable from getNextSequenceId
                 * @param signature see Data Formats
                 */
                function sendMultiSigBatch(
                  address[] calldata recipients,
                  uint256[] calldata values,
                  uint256 expireTime,
                  uint256 sequenceId,
                  bytes calldata signature
                ) external onlySigner {
                  require(recipients.length != 0, 'Not enough recipients');
                  require(
                    recipients.length == values.length,
                    'Unequal recipients and values'
                  );
                  require(recipients.length < 256, 'Too many recipients, max 255');
                  // Verify the other signer
                  bytes32 operationHash = keccak256(
                    abi.encodePacked(
                      getBatchNetworkId(),
                      recipients,
                      values,
                      expireTime,
                      sequenceId
                    )
                  );
                  // the first parameter (toAddress) is used to ensure transactions in safe mode only go to a signer
                  // if in safe mode, we should use normal sendMultiSig to recover, so this check will always fail if in safe mode
                  require(!safeMode, 'Batch in safe mode');
                  address otherSigner = verifyMultiSig(
                    address(0x0),
                    operationHash,
                    signature,
                    expireTime,
                    sequenceId
                  );
                  batchTransfer(recipients, values);
                  emit BatchTransacted(msg.sender, otherSigner, operationHash);
                }
                /**
                 * Transfer funds in a batch to each of recipients
                 * @param recipients The list of recipients to send to
                 * @param values The list of values to send to recipients.
                 *  The recipient with index i in recipients array will be sent values[i].
                 *  Thus, recipients and values must be the same length
                 */
                function batchTransfer(
                  address[] calldata recipients,
                  uint256[] calldata values
                ) internal {
                  for (uint256 i = 0; i < recipients.length; i++) {
                    require(address(this).balance >= values[i], 'Insufficient funds');
                    (bool success, ) = recipients[i].call{ value: values[i] }('');
                    require(success, 'Call failed');
                    emit BatchTransfer(msg.sender, recipients[i], values[i]);
                  }
                }
                /**
                 * Execute a multi-signature token transfer from this wallet using 2 signers: one from msg.sender and the other from ecrecover.
                 * Sequence IDs are numbers starting from 1. They are used to prevent replay attacks and may not be repeated.
                 *
                 * @param toAddress the destination address to send an outgoing transaction
                 * @param value the amount in tokens to be sent
                 * @param tokenContractAddress the address of the erc20 token contract
                 * @param expireTime the number of seconds since 1970 for which this transaction is valid
                 * @param sequenceId the unique sequence id obtainable from getNextSequenceId
                 * @param signature see Data Formats
                 */
                function sendMultiSigToken(
                  address toAddress,
                  uint256 value,
                  address tokenContractAddress,
                  uint256 expireTime,
                  uint256 sequenceId,
                  bytes calldata signature
                ) external onlySigner {
                  // Verify the other signer
                  bytes32 operationHash = keccak256(
                    abi.encodePacked(
                      getTokenNetworkId(),
                      toAddress,
                      value,
                      tokenContractAddress,
                      expireTime,
                      sequenceId
                    )
                  );
                  verifyMultiSig(toAddress, operationHash, signature, expireTime, sequenceId);
                  TransferHelper.safeTransfer(tokenContractAddress, toAddress, value);
                }
                /**
                 * Execute a token flush from one of the forwarder addresses. This transfer needs only a single signature and can be done by any signer
                 *
                 * @param forwarderAddress the address of the forwarder address to flush the tokens from
                 * @param tokenContractAddress the address of the erc20 token contract
                 */
                function flushForwarderTokens(
                  address payable forwarderAddress,
                  address tokenContractAddress
                ) external onlySigner {
                  IForwarder forwarder = IForwarder(forwarderAddress);
                  forwarder.flushTokens(tokenContractAddress);
                }
                /**
                 * Execute a ERC721 token flush from one of the forwarder addresses. This transfer needs only a single signature and can be done by any signer
                 *
                 * @param forwarderAddress the address of the forwarder address to flush the tokens from
                 * @param tokenContractAddress the address of the erc20 token contract
                 */
                function flushERC721ForwarderTokens(
                  address payable forwarderAddress,
                  address tokenContractAddress,
                  uint256 tokenId
                ) external onlySigner {
                  IForwarder forwarder = IForwarder(forwarderAddress);
                  forwarder.flushERC721Token(tokenContractAddress, tokenId);
                }
                /**
                 * Execute a ERC1155 batch token flush from one of the forwarder addresses.
                 * This transfer needs only a single signature and can be done by any signer.
                 *
                 * @param forwarderAddress the address of the forwarder address to flush the tokens from
                 * @param tokenContractAddress the address of the erc1155 token contract
                 */
                function batchFlushERC1155ForwarderTokens(
                  address payable forwarderAddress,
                  address tokenContractAddress,
                  uint256[] calldata tokenIds
                ) external onlySigner {
                  IForwarder forwarder = IForwarder(forwarderAddress);
                  forwarder.batchFlushERC1155Tokens(tokenContractAddress, tokenIds);
                }
                /**
                 * Execute a ERC1155 token flush from one of the forwarder addresses.
                 * This transfer needs only a single signature and can be done by any signer.
                 *
                 * @param forwarderAddress the address of the forwarder address to flush the tokens from
                 * @param tokenContractAddress the address of the erc1155 token contract
                 * @param tokenId the token id associated with the ERC1155
                 */
                function flushERC1155ForwarderTokens(
                  address payable forwarderAddress,
                  address tokenContractAddress,
                  uint256 tokenId
                ) external onlySigner {
                  IForwarder forwarder = IForwarder(forwarderAddress);
                  forwarder.flushERC1155Tokens(tokenContractAddress, tokenId);
                }
                /**
                 * Sets the autoflush 721 parameter on the forwarder.
                 *
                 * @param forwarderAddress the address of the forwarder to toggle.
                 * @param autoFlush whether to autoflush erc721 tokens
                 */
                function setAutoFlush721(address forwarderAddress, bool autoFlush)
                  external
                  onlySigner
                {
                  IForwarder forwarder = IForwarder(forwarderAddress);
                  forwarder.setAutoFlush721(autoFlush);
                }
                /**
                 * Sets the autoflush 721 parameter on the forwarder.
                 *
                 * @param forwarderAddress the address of the forwarder to toggle.
                 * @param autoFlush whether to autoflush erc1155 tokens
                 */
                function setAutoFlush1155(address forwarderAddress, bool autoFlush)
                  external
                  onlySigner
                {
                  IForwarder forwarder = IForwarder(forwarderAddress);
                  forwarder.setAutoFlush1155(autoFlush);
                }
                /**
                 * Do common multisig verification for both eth sends and erc20token transfers
                 *
                 * @param toAddress the destination address to send an outgoing transaction
                 * @param operationHash see Data Formats
                 * @param signature see Data Formats
                 * @param expireTime the number of seconds since 1970 for which this transaction is valid
                 * @param sequenceId the unique sequence id obtainable from getNextSequenceId
                 * returns address that has created the signature
                 */
                function verifyMultiSig(
                  address toAddress,
                  bytes32 operationHash,
                  bytes calldata signature,
                  uint256 expireTime,
                  uint256 sequenceId
                ) private returns (address) {
                  address otherSigner = recoverAddressFromSignature(operationHash, signature);
                  // Verify if we are in safe mode. In safe mode, the wallet can only send to signers
                  require(!safeMode || isSigner(toAddress), 'External transfer in safe mode');
                  // Verify that the transaction has not expired
                  require(expireTime >= block.timestamp, 'Transaction expired');
                  // Try to insert the sequence ID. Will revert if the sequence id was invalid
                  tryInsertSequenceId(sequenceId);
                  require(isSigner(otherSigner), 'Invalid signer');
                  require(otherSigner != msg.sender, 'Signers cannot be equal');
                  return otherSigner;
                }
                /**
                 * ERC721 standard callback function for when a ERC721 is transfered.
                 *
                 * @param _operator The address of the nft contract
                 * @param _from The address of the sender
                 * @param _tokenId The token id of the nft
                 * @param _data Additional data with no specified format, sent in call to `_to`
                 */
                function onERC721Received(
                  address _operator,
                  address _from,
                  uint256 _tokenId,
                  bytes memory _data
                ) external virtual override returns (bytes4) {
                  return this.onERC721Received.selector;
                }
                /**
                 * @inheritdoc IERC1155Receiver
                 */
                function onERC1155Received(
                  address _operator,
                  address _from,
                  uint256 id,
                  uint256 value,
                  bytes calldata data
                ) external virtual override returns (bytes4) {
                  return this.onERC1155Received.selector;
                }
                /**
                 * @inheritdoc IERC1155Receiver
                 */
                function onERC1155BatchReceived(
                  address _operator,
                  address _from,
                  uint256[] calldata ids,
                  uint256[] calldata values,
                  bytes calldata data
                ) external virtual override returns (bytes4) {
                  return this.onERC1155BatchReceived.selector;
                }
                /**
                 * Irrevocably puts contract into safe mode. When in this mode, transactions may only be sent to signing addresses.
                 */
                function activateSafeMode() external onlySigner {
                  safeMode = true;
                  emit SafeModeActivated(msg.sender);
                }
                /**
                 * Gets signer's address using ecrecover
                 * @param operationHash see Data Formats
                 * @param signature see Data Formats
                 * returns address recovered from the signature
                 */
                function recoverAddressFromSignature(
                  bytes32 operationHash,
                  bytes memory signature
                ) private pure returns (address) {
                  require(signature.length == 65, 'Invalid signature - wrong length');
                  // We need to unpack the signature, which is given as an array of 65 bytes (like eth.sign)
                  bytes32 r;
                  bytes32 s;
                  uint8 v;
                  // solhint-disable-next-line
                  assembly {
                    r := mload(add(signature, 32))
                    s := mload(add(signature, 64))
                    v := and(mload(add(signature, 65)), 255)
                  }
                  if (v < 27) {
                    v += 27; // Ethereum versions are 27 or 28 as opposed to 0 or 1 which is submitted by some signing libs
                  }
                  // protect against signature malleability
                  // S value must be in the lower half orader
                  // reference: https://github.com/OpenZeppelin/openzeppelin-contracts/blob/051d340171a93a3d401aaaea46b4b62fa81e5d7c/contracts/cryptography/ECDSA.sol#L53
                  require(
                    uint256(s) <=
                      0x7FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF5D576E7357A4501DDFE92F46681B20A0,
                    "ECDSA: invalid signature 's' value"
                  );
                  // note that this returns 0 if the signature is invalid
                  // Since 0x0 can never be a signer, when the recovered signer address
                  // is checked against our signer list, that 0x0 will cause an invalid signer failure
                  return ecrecover(operationHash, v, r, s);
                }
                /**
                 * Verify that the sequence id has not been used before and inserts it. Throws if the sequence ID was not accepted.
                 * We collect a window of up to 10 recent sequence ids, and allow any sequence id that is not in the window and
                 * greater than the minimum element in the window.
                 * @param sequenceId to insert into array of stored ids
                 */
                function tryInsertSequenceId(uint256 sequenceId) private onlySigner {
                  // Keep a pointer to the lowest value element in the window
                  uint256 lowestValueIndex = 0;
                  // fetch recentSequenceIds into memory for function context to avoid unnecessary sloads
                    uint256[SEQUENCE_ID_WINDOW_SIZE] memory _recentSequenceIds
                   = recentSequenceIds;
                  for (uint256 i = 0; i < SEQUENCE_ID_WINDOW_SIZE; i++) {
                    require(_recentSequenceIds[i] != sequenceId, 'Sequence ID already used');
                    if (_recentSequenceIds[i] < _recentSequenceIds[lowestValueIndex]) {
                      lowestValueIndex = i;
                    }
                  }
                  // The sequence ID being used is lower than the lowest value in the window
                  // so we cannot accept it as it may have been used before
                  require(
                    sequenceId > _recentSequenceIds[lowestValueIndex],
                    'Sequence ID below window'
                  );
                  // Block sequence IDs which are much higher than the lowest value
                  // This prevents people blocking the contract by using very large sequence IDs quickly
                  require(
                    sequenceId <=
                      (_recentSequenceIds[lowestValueIndex] + MAX_SEQUENCE_ID_INCREASE),
                    'Sequence ID above maximum'
                  );
                  recentSequenceIds[lowestValueIndex] = sequenceId;
                }
                /**
                 * Gets the next available sequence ID for signing when using executeAndConfirm
                 * returns the sequenceId one higher than the highest currently stored
                 */
                function getNextSequenceId() external view returns (uint256) {
                  uint256 highestSequenceId = 0;
                  for (uint256 i = 0; i < SEQUENCE_ID_WINDOW_SIZE; i++) {
                    if (recentSequenceIds[i] > highestSequenceId) {
                      highestSequenceId = recentSequenceIds[i];
                    }
                  }
                  return highestSequenceId + 1;
                }
              }
              // SPDX-License-Identifier: GPL-3.0-or-later
              // source: https://github.com/Uniswap/solidity-lib/blob/master/contracts/libraries/TransferHelper.sol
              pragma solidity 0.8.10;
              import '@openzeppelin/contracts/utils/Address.sol';
              // helper methods for interacting with ERC20 tokens and sending ETH that do not consistently return true/false
              library TransferHelper {
                function safeTransfer(
                  address token,
                  address to,
                  uint256 value
                ) internal {
                  // bytes4(keccak256(bytes('transfer(address,uint256)')));
                  (bool success, bytes memory data) = token.call(
                    abi.encodeWithSelector(0xa9059cbb, to, value)
                  );
                  require(
                    success && (data.length == 0 || abi.decode(data, (bool))),
                    'TransferHelper::safeTransfer: transfer failed'
                  );
                }
                function safeTransferFrom(
                  address token,
                  address from,
                  address to,
                  uint256 value
                ) internal {
                  // bytes4(keccak256(bytes('transferFrom(address,address,uint256)')));
                  (bool success, bytes memory returndata) = token.call(
                    abi.encodeWithSelector(0x23b872dd, from, to, value)
                  );
                  Address.verifyCallResult(
                    success,
                    returndata,
                    'TransferHelper::transferFrom: transferFrom failed'
                  );
                }
              }
              // SPDX-License-Identifier: UNLICENSED
              pragma solidity 0.8.10;
              /**
               * Contract that exposes the needed erc20 token functions
               */
              abstract contract ERC20Interface {
                // Send _value amount of tokens to address _to
                function transfer(address _to, uint256 _value)
                  public
                  virtual
                  returns (bool success);
                // Get the account balance of another account with address _owner
                function balanceOf(address _owner)
                  public
                  virtual
                  view
                  returns (uint256 balance);
              }
              pragma solidity ^0.8.0;
              import '@openzeppelin/contracts/utils/introspection/IERC165.sol';
              interface IForwarder is IERC165 {
                /**
                 * Sets the autoflush721 parameter.
                 *
                 * @param autoFlush whether to autoflush erc721 tokens
                 */
                function setAutoFlush721(bool autoFlush) external;
                /**
                 * Sets the autoflush1155 parameter.
                 *
                 * @param autoFlush whether to autoflush erc1155 tokens
                 */
                function setAutoFlush1155(bool autoFlush) external;
                /**
                 * Execute a token transfer of the full balance from the forwarder token to the parent address
                 *
                 * @param tokenContractAddress the address of the erc20 token contract
                 */
                function flushTokens(address tokenContractAddress) external;
                /**
                 * Execute a nft transfer from the forwarder to the parent address
                 *
                 * @param tokenContractAddress the address of the ERC721 NFT contract
                 * @param tokenId The token id of the nft
                 */
                function flushERC721Token(address tokenContractAddress, uint256 tokenId)
                  external;
                /**
                 * Execute a nft transfer from the forwarder to the parent address.
                 *
                 * @param tokenContractAddress the address of the ERC1155 NFT contract
                 * @param tokenId The token id of the nft
                 */
                function flushERC1155Tokens(address tokenContractAddress, uint256 tokenId)
                  external;
                /**
                 * Execute a batch nft transfer from the forwarder to the parent address.
                 *
                 * @param tokenContractAddress the address of the ERC1155 NFT contract
                 * @param tokenIds The token ids of the nfts
                 */
                function batchFlushERC1155Tokens(
                  address tokenContractAddress,
                  uint256[] calldata tokenIds
                ) external;
              }
              // SPDX-License-Identifier: MIT
              // OpenZeppelin Contracts v4.4.1 (token/ERC721/IERC721Receiver.sol)
              pragma solidity ^0.8.0;
              /**
               * @title ERC721 token receiver interface
               * @dev Interface for any contract that wants to support safeTransfers
               * from ERC721 asset contracts.
               */
              interface IERC721Receiver {
                  /**
                   * @dev Whenever an {IERC721} `tokenId` token is transferred to this contract via {IERC721-safeTransferFrom}
                   * by `operator` from `from`, this function is called.
                   *
                   * It must return its Solidity selector to confirm the token transfer.
                   * If any other value is returned or the interface is not implemented by the recipient, the transfer will be reverted.
                   *
                   * The selector can be obtained in Solidity with `IERC721.onERC721Received.selector`.
                   */
                  function onERC721Received(
                      address operator,
                      address from,
                      uint256 tokenId,
                      bytes calldata data
                  ) external returns (bytes4);
              }
              // SPDX-License-Identifier: MIT
              // OpenZeppelin Contracts v4.4.1 (token/ERC1155/utils/ERC1155Receiver.sol)
              pragma solidity ^0.8.0;
              import "../IERC1155Receiver.sol";
              import "../../../utils/introspection/ERC165.sol";
              /**
               * @dev _Available since v3.1._
               */
              abstract contract ERC1155Receiver is ERC165, IERC1155Receiver {
                  /**
                   * @dev See {IERC165-supportsInterface}.
                   */
                  function supportsInterface(bytes4 interfaceId) public view virtual override(ERC165, IERC165) returns (bool) {
                      return interfaceId == type(IERC1155Receiver).interfaceId || super.supportsInterface(interfaceId);
                  }
              }
              // SPDX-License-Identifier: MIT
              // OpenZeppelin Contracts v4.4.1 (utils/Address.sol)
              pragma solidity ^0.8.0;
              /**
               * @dev Collection of functions related to the address type
               */
              library Address {
                  /**
                   * @dev Returns true if `account` is a contract.
                   *
                   * [IMPORTANT]
                   * ====
                   * It is unsafe to assume that an address for which this function returns
                   * false is an externally-owned account (EOA) and not a contract.
                   *
                   * Among others, `isContract` will return false for the following
                   * types of addresses:
                   *
                   *  - an externally-owned account
                   *  - a contract in construction
                   *  - an address where a contract will be created
                   *  - an address where a contract lived, but was destroyed
                   * ====
                   */
                  function isContract(address account) internal view returns (bool) {
                      // This method relies on extcodesize, which returns 0 for contracts in
                      // construction, since the code is only stored at the end of the
                      // constructor execution.
                      uint256 size;
                      assembly {
                          size := extcodesize(account)
                      }
                      return size > 0;
                  }
                  /**
                   * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
                   * `recipient`, forwarding all available gas and reverting on errors.
                   *
                   * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
                   * of certain opcodes, possibly making contracts go over the 2300 gas limit
                   * imposed by `transfer`, making them unable to receive funds via
                   * `transfer`. {sendValue} removes this limitation.
                   *
                   * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
                   *
                   * IMPORTANT: because control is transferred to `recipient`, care must be
                   * taken to not create reentrancy vulnerabilities. Consider using
                   * {ReentrancyGuard} or the
                   * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
                   */
                  function sendValue(address payable recipient, uint256 amount) internal {
                      require(address(this).balance >= amount, "Address: insufficient balance");
                      (bool success, ) = recipient.call{value: amount}("");
                      require(success, "Address: unable to send value, recipient may have reverted");
                  }
                  /**
                   * @dev Performs a Solidity function call using a low level `call`. A
                   * plain `call` is an unsafe replacement for a function call: use this
                   * function instead.
                   *
                   * If `target` reverts with a revert reason, it is bubbled up by this
                   * function (like regular Solidity function calls).
                   *
                   * Returns the raw returned data. To convert to the expected return value,
                   * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
                   *
                   * Requirements:
                   *
                   * - `target` must be a contract.
                   * - calling `target` with `data` must not revert.
                   *
                   * _Available since v3.1._
                   */
                  function functionCall(address target, bytes memory data) internal returns (bytes memory) {
                      return functionCall(target, data, "Address: low-level call failed");
                  }
                  /**
                   * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
                   * `errorMessage` as a fallback revert reason when `target` reverts.
                   *
                   * _Available since v3.1._
                   */
                  function functionCall(
                      address target,
                      bytes memory data,
                      string memory errorMessage
                  ) internal returns (bytes memory) {
                      return functionCallWithValue(target, data, 0, errorMessage);
                  }
                  /**
                   * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
                   * but also transferring `value` wei to `target`.
                   *
                   * Requirements:
                   *
                   * - the calling contract must have an ETH balance of at least `value`.
                   * - the called Solidity function must be `payable`.
                   *
                   * _Available since v3.1._
                   */
                  function functionCallWithValue(
                      address target,
                      bytes memory data,
                      uint256 value
                  ) internal returns (bytes memory) {
                      return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
                  }
                  /**
                   * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
                   * with `errorMessage` as a fallback revert reason when `target` reverts.
                   *
                   * _Available since v3.1._
                   */
                  function functionCallWithValue(
                      address target,
                      bytes memory data,
                      uint256 value,
                      string memory errorMessage
                  ) internal returns (bytes memory) {
                      require(address(this).balance >= value, "Address: insufficient balance for call");
                      require(isContract(target), "Address: call to non-contract");
                      (bool success, bytes memory returndata) = target.call{value: value}(data);
                      return verifyCallResult(success, returndata, errorMessage);
                  }
                  /**
                   * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
                   * but performing a static call.
                   *
                   * _Available since v3.3._
                   */
                  function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
                      return functionStaticCall(target, data, "Address: low-level static call failed");
                  }
                  /**
                   * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
                   * but performing a static call.
                   *
                   * _Available since v3.3._
                   */
                  function functionStaticCall(
                      address target,
                      bytes memory data,
                      string memory errorMessage
                  ) internal view returns (bytes memory) {
                      require(isContract(target), "Address: static call to non-contract");
                      (bool success, bytes memory returndata) = target.staticcall(data);
                      return verifyCallResult(success, returndata, errorMessage);
                  }
                  /**
                   * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
                   * but performing a delegate call.
                   *
                   * _Available since v3.4._
                   */
                  function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {
                      return functionDelegateCall(target, data, "Address: low-level delegate call failed");
                  }
                  /**
                   * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
                   * but performing a delegate call.
                   *
                   * _Available since v3.4._
                   */
                  function functionDelegateCall(
                      address target,
                      bytes memory data,
                      string memory errorMessage
                  ) internal returns (bytes memory) {
                      require(isContract(target), "Address: delegate call to non-contract");
                      (bool success, bytes memory returndata) = target.delegatecall(data);
                      return verifyCallResult(success, returndata, errorMessage);
                  }
                  /**
                   * @dev Tool to verifies that a low level call was successful, and revert if it wasn't, either by bubbling the
                   * revert reason using the provided one.
                   *
                   * _Available since v4.3._
                   */
                  function verifyCallResult(
                      bool success,
                      bytes memory returndata,
                      string memory errorMessage
                  ) internal pure returns (bytes memory) {
                      if (success) {
                          return returndata;
                      } else {
                          // Look for revert reason and bubble it up if present
                          if (returndata.length > 0) {
                              // The easiest way to bubble the revert reason is using memory via assembly
                              assembly {
                                  let returndata_size := mload(returndata)
                                  revert(add(32, returndata), returndata_size)
                              }
                          } else {
                              revert(errorMessage);
                          }
                      }
                  }
              }
              // SPDX-License-Identifier: MIT
              // OpenZeppelin Contracts v4.4.1 (utils/introspection/IERC165.sol)
              pragma solidity ^0.8.0;
              /**
               * @dev Interface of the ERC165 standard, as defined in the
               * https://eips.ethereum.org/EIPS/eip-165[EIP].
               *
               * Implementers can declare support of contract interfaces, which can then be
               * queried by others ({ERC165Checker}).
               *
               * For an implementation, see {ERC165}.
               */
              interface IERC165 {
                  /**
                   * @dev Returns true if this contract implements the interface defined by
                   * `interfaceId`. See the corresponding
                   * https://eips.ethereum.org/EIPS/eip-165#how-interfaces-are-identified[EIP section]
                   * to learn more about how these ids are created.
                   *
                   * This function call must use less than 30 000 gas.
                   */
                  function supportsInterface(bytes4 interfaceId) external view returns (bool);
              }
              // SPDX-License-Identifier: MIT
              // OpenZeppelin Contracts v4.4.1 (token/ERC1155/IERC1155Receiver.sol)
              pragma solidity ^0.8.0;
              import "../../utils/introspection/IERC165.sol";
              /**
               * @dev _Available since v3.1._
               */
              interface IERC1155Receiver is IERC165 {
                  /**
                      @dev Handles the receipt of a single ERC1155 token type. This function is
                      called at the end of a `safeTransferFrom` after the balance has been updated.
                      To accept the transfer, this must return
                      `bytes4(keccak256("onERC1155Received(address,address,uint256,uint256,bytes)"))`
                      (i.e. 0xf23a6e61, or its own function selector).
                      @param operator The address which initiated the transfer (i.e. msg.sender)
                      @param from The address which previously owned the token
                      @param id The ID of the token being transferred
                      @param value The amount of tokens being transferred
                      @param data Additional data with no specified format
                      @return `bytes4(keccak256("onERC1155Received(address,address,uint256,uint256,bytes)"))` if transfer is allowed
                  */
                  function onERC1155Received(
                      address operator,
                      address from,
                      uint256 id,
                      uint256 value,
                      bytes calldata data
                  ) external returns (bytes4);
                  /**
                      @dev Handles the receipt of a multiple ERC1155 token types. This function
                      is called at the end of a `safeBatchTransferFrom` after the balances have
                      been updated. To accept the transfer(s), this must return
                      `bytes4(keccak256("onERC1155BatchReceived(address,address,uint256[],uint256[],bytes)"))`
                      (i.e. 0xbc197c81, or its own function selector).
                      @param operator The address which initiated the batch transfer (i.e. msg.sender)
                      @param from The address which previously owned the token
                      @param ids An array containing ids of each token being transferred (order and length must match values array)
                      @param values An array containing amounts of each token being transferred (order and length must match ids array)
                      @param data Additional data with no specified format
                      @return `bytes4(keccak256("onERC1155BatchReceived(address,address,uint256[],uint256[],bytes)"))` if transfer is allowed
                  */
                  function onERC1155BatchReceived(
                      address operator,
                      address from,
                      uint256[] calldata ids,
                      uint256[] calldata values,
                      bytes calldata data
                  ) external returns (bytes4);
              }
              // SPDX-License-Identifier: MIT
              // OpenZeppelin Contracts v4.4.1 (utils/introspection/ERC165.sol)
              pragma solidity ^0.8.0;
              import "./IERC165.sol";
              /**
               * @dev Implementation of the {IERC165} interface.
               *
               * Contracts that want to implement ERC165 should inherit from this contract and override {supportsInterface} to check
               * for the additional interface id that will be supported. For example:
               *
               * ```solidity
               * function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
               *     return interfaceId == type(MyInterface).interfaceId || super.supportsInterface(interfaceId);
               * }
               * ```
               *
               * Alternatively, {ERC165Storage} provides an easier to use but more expensive implementation.
               */
              abstract contract ERC165 is IERC165 {
                  /**
                   * @dev See {IERC165-supportsInterface}.
                   */
                  function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
                      return interfaceId == type(IERC165).interfaceId;
                  }
              }
              

              File 2 of 5: FiatTokenProxy
              pragma solidity ^0.4.24;
              
              // File: zos-lib/contracts/upgradeability/Proxy.sol
              
              /**
               * @title Proxy
               * @dev Implements delegation of calls to other contracts, with proper
               * forwarding of return values and bubbling of failures.
               * It defines a fallback function that delegates all calls to the address
               * returned by the abstract _implementation() internal function.
               */
              contract Proxy {
                /**
                 * @dev Fallback function.
                 * Implemented entirely in `_fallback`.
                 */
                function () payable external {
                  _fallback();
                }
              
                /**
                 * @return The Address of the implementation.
                 */
                function _implementation() internal view returns (address);
              
                /**
                 * @dev Delegates execution to an implementation contract.
                 * This is a low level function that doesn't return to its internal call site.
                 * It will return to the external caller whatever the implementation returns.
                 * @param implementation Address to delegate.
                 */
                function _delegate(address implementation) internal {
                  assembly {
                    // Copy msg.data. We take full control of memory in this inline assembly
                    // block because it will not return to Solidity code. We overwrite the
                    // Solidity scratch pad at memory position 0.
                    calldatacopy(0, 0, calldatasize)
              
                    // Call the implementation.
                    // out and outsize are 0 because we don't know the size yet.
                    let result := delegatecall(gas, implementation, 0, calldatasize, 0, 0)
              
                    // Copy the returned data.
                    returndatacopy(0, 0, returndatasize)
              
                    switch result
                    // delegatecall returns 0 on error.
                    case 0 { revert(0, returndatasize) }
                    default { return(0, returndatasize) }
                  }
                }
              
                /**
                 * @dev Function that is run as the first thing in the fallback function.
                 * Can be redefined in derived contracts to add functionality.
                 * Redefinitions must call super._willFallback().
                 */
                function _willFallback() internal {
                }
              
                /**
                 * @dev fallback implementation.
                 * Extracted to enable manual triggering.
                 */
                function _fallback() internal {
                  _willFallback();
                  _delegate(_implementation());
                }
              }
              
              // File: openzeppelin-solidity/contracts/AddressUtils.sol
              
              /**
               * Utility library of inline functions on addresses
               */
              library AddressUtils {
              
                /**
                 * Returns whether the target address is a contract
                 * @dev This function will return false if invoked during the constructor of a contract,
                 * as the code is not actually created until after the constructor finishes.
                 * @param addr address to check
                 * @return whether the target address is a contract
                 */
                function isContract(address addr) internal view returns (bool) {
                  uint256 size;
                  // XXX Currently there is no better way to check if there is a contract in an address
                  // than to check the size of the code at that address.
                  // See https://ethereum.stackexchange.com/a/14016/36603
                  // for more details about how this works.
                  // TODO Check this again before the Serenity release, because all addresses will be
                  // contracts then.
                  // solium-disable-next-line security/no-inline-assembly
                  assembly { size := extcodesize(addr) }
                  return size > 0;
                }
              
              }
              
              // File: zos-lib/contracts/upgradeability/UpgradeabilityProxy.sol
              
              /**
               * @title UpgradeabilityProxy
               * @dev This contract implements a proxy that allows to change the
               * implementation address to which it will delegate.
               * Such a change is called an implementation upgrade.
               */
              contract UpgradeabilityProxy is Proxy {
                /**
                 * @dev Emitted when the implementation is upgraded.
                 * @param implementation Address of the new implementation.
                 */
                event Upgraded(address implementation);
              
                /**
                 * @dev Storage slot with the address of the current implementation.
                 * This is the keccak-256 hash of "org.zeppelinos.proxy.implementation", and is
                 * validated in the constructor.
                 */
                bytes32 private constant IMPLEMENTATION_SLOT = 0x7050c9e0f4ca769c69bd3a8ef740bc37934f8e2c036e5a723fd8ee048ed3f8c3;
              
                /**
                 * @dev Contract constructor.
                 * @param _implementation Address of the initial implementation.
                 */
                constructor(address _implementation) public {
                  assert(IMPLEMENTATION_SLOT == keccak256("org.zeppelinos.proxy.implementation"));
              
                  _setImplementation(_implementation);
                }
              
                /**
                 * @dev Returns the current implementation.
                 * @return Address of the current implementation
                 */
                function _implementation() internal view returns (address impl) {
                  bytes32 slot = IMPLEMENTATION_SLOT;
                  assembly {
                    impl := sload(slot)
                  }
                }
              
                /**
                 * @dev Upgrades the proxy to a new implementation.
                 * @param newImplementation Address of the new implementation.
                 */
                function _upgradeTo(address newImplementation) internal {
                  _setImplementation(newImplementation);
                  emit Upgraded(newImplementation);
                }
              
                /**
                 * @dev Sets the implementation address of the proxy.
                 * @param newImplementation Address of the new implementation.
                 */
                function _setImplementation(address newImplementation) private {
                  require(AddressUtils.isContract(newImplementation), "Cannot set a proxy implementation to a non-contract address");
              
                  bytes32 slot = IMPLEMENTATION_SLOT;
              
                  assembly {
                    sstore(slot, newImplementation)
                  }
                }
              }
              
              // File: zos-lib/contracts/upgradeability/AdminUpgradeabilityProxy.sol
              
              /**
               * @title AdminUpgradeabilityProxy
               * @dev This contract combines an upgradeability proxy with an authorization
               * mechanism for administrative tasks.
               * All external functions in this contract must be guarded by the
               * `ifAdmin` modifier. See ethereum/solidity#3864 for a Solidity
               * feature proposal that would enable this to be done automatically.
               */
              contract AdminUpgradeabilityProxy is UpgradeabilityProxy {
                /**
                 * @dev Emitted when the administration has been transferred.
                 * @param previousAdmin Address of the previous admin.
                 * @param newAdmin Address of the new admin.
                 */
                event AdminChanged(address previousAdmin, address newAdmin);
              
                /**
                 * @dev Storage slot with the admin of the contract.
                 * This is the keccak-256 hash of "org.zeppelinos.proxy.admin", and is
                 * validated in the constructor.
                 */
                bytes32 private constant ADMIN_SLOT = 0x10d6a54a4754c8869d6886b5f5d7fbfa5b4522237ea5c60d11bc4e7a1ff9390b;
              
                /**
                 * @dev Modifier to check whether the `msg.sender` is the admin.
                 * If it is, it will run the function. Otherwise, it will delegate the call
                 * to the implementation.
                 */
                modifier ifAdmin() {
                  if (msg.sender == _admin()) {
                    _;
                  } else {
                    _fallback();
                  }
                }
              
                /**
                 * Contract constructor.
                 * It sets the `msg.sender` as the proxy administrator.
                 * @param _implementation address of the initial implementation.
                 */
                constructor(address _implementation) UpgradeabilityProxy(_implementation) public {
                  assert(ADMIN_SLOT == keccak256("org.zeppelinos.proxy.admin"));
              
                  _setAdmin(msg.sender);
                }
              
                /**
                 * @return The address of the proxy admin.
                 */
                function admin() external view ifAdmin returns (address) {
                  return _admin();
                }
              
                /**
                 * @return The address of the implementation.
                 */
                function implementation() external view ifAdmin returns (address) {
                  return _implementation();
                }
              
                /**
                 * @dev Changes the admin of the proxy.
                 * Only the current admin can call this function.
                 * @param newAdmin Address to transfer proxy administration to.
                 */
                function changeAdmin(address newAdmin) external ifAdmin {
                  require(newAdmin != address(0), "Cannot change the admin of a proxy to the zero address");
                  emit AdminChanged(_admin(), newAdmin);
                  _setAdmin(newAdmin);
                }
              
                /**
                 * @dev Upgrade the backing implementation of the proxy.
                 * Only the admin can call this function.
                 * @param newImplementation Address of the new implementation.
                 */
                function upgradeTo(address newImplementation) external ifAdmin {
                  _upgradeTo(newImplementation);
                }
              
                /**
                 * @dev Upgrade the backing implementation of the proxy and call a function
                 * on the new implementation.
                 * This is useful to initialize the proxied contract.
                 * @param newImplementation Address of the new implementation.
                 * @param data Data to send as msg.data in the low level call.
                 * It should include the signature and the parameters of the function to be
                 * called, as described in
                 * https://solidity.readthedocs.io/en/develop/abi-spec.html#function-selector-and-argument-encoding.
                 */
                function upgradeToAndCall(address newImplementation, bytes data) payable external ifAdmin {
                  _upgradeTo(newImplementation);
                  require(address(this).call.value(msg.value)(data));
                }
              
                /**
                 * @return The admin slot.
                 */
                function _admin() internal view returns (address adm) {
                  bytes32 slot = ADMIN_SLOT;
                  assembly {
                    adm := sload(slot)
                  }
                }
              
                /**
                 * @dev Sets the address of the proxy admin.
                 * @param newAdmin Address of the new proxy admin.
                 */
                function _setAdmin(address newAdmin) internal {
                  bytes32 slot = ADMIN_SLOT;
              
                  assembly {
                    sstore(slot, newAdmin)
                  }
                }
              
                /**
                 * @dev Only fall back when the sender is not the admin.
                 */
                function _willFallback() internal {
                  require(msg.sender != _admin(), "Cannot call fallback function from the proxy admin");
                  super._willFallback();
                }
              }
              
              // File: contracts/FiatTokenProxy.sol
              
              /**
              * Copyright CENTRE SECZ 2018
              *
              * Permission is hereby granted, free of charge, to any person obtaining a copy 
              * of this software and associated documentation files (the "Software"), to deal 
              * in the Software without restriction, including without limitation the rights 
              * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell 
              * copies of the Software, and to permit persons to whom the Software is furnished to 
              * do so, subject to the following conditions:
              *
              * The above copyright notice and this permission notice shall be included in all 
              * copies or substantial portions of the Software.
              *
              * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 
              * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 
              * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE 
              * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
              * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN 
              * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
              */
              
              pragma solidity ^0.4.24;
              
              
              /**
               * @title FiatTokenProxy
               * @dev This contract proxies FiatToken calls and enables FiatToken upgrades
              */ 
              contract FiatTokenProxy is AdminUpgradeabilityProxy {
                  constructor(address _implementation) public AdminUpgradeabilityProxy(_implementation) {
                  }
              }

              File 3 of 5: WalletSimple
              // SPDX-License-Identifier: Apache-2.0
              pragma solidity 0.8.10;
              import './TransferHelper.sol';
              import './ERC20Interface.sol';
              import './IForwarder.sol';
              /** ERC721, ERC1155 imports */
              import '@openzeppelin/contracts/token/ERC721/IERC721Receiver.sol';
              import '@openzeppelin/contracts/token/ERC1155/utils/ERC1155Receiver.sol';
              /**
               *
               * WalletSimple
               * ============
               *
               * Basic multi-signer wallet designed for use in a co-signing environment where 2 signatures are required to move funds.
               * Typically used in a 2-of-3 signing configuration. Uses ecrecover to allow for 2 signatures in a single transaction.
               *
               * The first signature is created on the operation hash (see Data Formats) and passed to sendMultiSig/sendMultiSigToken
               * The signer is determined by verifyMultiSig().
               *
               * The second signature is created by the submitter of the transaction and determined by msg.signer.
               *
               * Data Formats
               * ============
               *
               * The signature is created with ethereumjs-util.ecsign(operationHash).
               * Like the eth_sign RPC call, it packs the values as a 65-byte array of [r, s, v].
               * Unlike eth_sign, the message is not prefixed.
               *
               * The operationHash the result of keccak256(prefix, toAddress, value, data, expireTime).
               * For ether transactions, `prefix` is "ETHER".
               * For token transaction, `prefix` is "ERC20" and `data` is the tokenContractAddress.
               *
               *
               */
              contract WalletSimple is IERC721Receiver, ERC1155Receiver {
                // Events
                event Deposited(address from, uint256 value, bytes data);
                event SafeModeActivated(address msgSender);
                event Transacted(
                  address msgSender, // Address of the sender of the message initiating the transaction
                  address otherSigner, // Address of the signer (second signature) used to initiate the transaction
                  bytes32 operation, // Operation hash (see Data Formats)
                  address toAddress, // The address the transaction was sent to
                  uint256 value, // Amount of Wei sent to the address
                  bytes data // Data sent when invoking the transaction
                );
                event BatchTransfer(address sender, address recipient, uint256 value);
                // this event shows the other signer and the operation hash that they signed
                // specific batch transfer events are emitted in Batcher
                event BatchTransacted(
                  address msgSender, // Address of the sender of the message initiating the transaction
                  address otherSigner, // Address of the signer (second signature) used to initiate the transaction
                  bytes32 operation // Operation hash (see Data Formats)
                );
                // Public fields
                mapping(address => bool) public signers; // The addresses that can co-sign transactions on the wallet
                bool public safeMode = false; // When active, wallet may only send to signer addresses
                bool public initialized = false; // True if the contract has been initialized
                // Internal fields
                uint256 private constant MAX_SEQUENCE_ID_INCREASE = 10000;
                uint256 constant SEQUENCE_ID_WINDOW_SIZE = 10;
                uint256[SEQUENCE_ID_WINDOW_SIZE] recentSequenceIds;
                /**
                 * Set up a simple multi-sig wallet by specifying the signers allowed to be used on this wallet.
                 * 2 signers will be required to send a transaction from this wallet.
                 * Note: The sender is NOT automatically added to the list of signers.
                 * Signers CANNOT be changed once they are set
                 *
                 * @param allowedSigners An array of signers on the wallet
                 */
                function init(address[] calldata allowedSigners) external onlyUninitialized {
                  require(allowedSigners.length == 3, 'Invalid number of signers');
                  for (uint8 i = 0; i < allowedSigners.length; i++) {
                    require(allowedSigners[i] != address(0), 'Invalid signer');
                    signers[allowedSigners[i]] = true;
                  }
                  initialized = true;
                }
                /**
                 * Get the network identifier that signers must sign over
                 * This provides protection signatures being replayed on other chains
                 * This must be a virtual function because chain-specific contracts will need
                 *    to override with their own network ids. It also can't be a field
                 *    to allow this contract to be used by proxy with delegatecall, which will
                 *    not pick up on state variables
                 */
                function getNetworkId() internal virtual pure returns (string memory) {
                  return 'ETHER';
                }
                /**
                 * Get the network identifier that signers must sign over for token transfers
                 * This provides protection signatures being replayed on other chains
                 * This must be a virtual function because chain-specific contracts will need
                 *    to override with their own network ids. It also can't be a field
                 *    to allow this contract to be used by proxy with delegatecall, which will
                 *    not pick up on state variables
                 */
                function getTokenNetworkId() internal virtual pure returns (string memory) {
                  return 'ERC20';
                }
                /**
                 * Get the network identifier that signers must sign over for batch transfers
                 * This provides protection signatures being replayed on other chains
                 * This must be a virtual function because chain-specific contracts will need
                 *    to override with their own network ids. It also can't be a field
                 *    to allow this contract to be used by proxy with delegatecall, which will
                 *    not pick up on state variables
                 */
                function getBatchNetworkId() internal virtual pure returns (string memory) {
                  return 'ETHER-Batch';
                }
                /**
                 * Determine if an address is a signer on this wallet
                 * @param signer address to check
                 * returns boolean indicating whether address is signer or not
                 */
                function isSigner(address signer) public view returns (bool) {
                  return signers[signer];
                }
                /**
                 * Modifier that will execute internal code block only if the sender is an authorized signer on this wallet
                 */
                modifier onlySigner {
                  require(isSigner(msg.sender), 'Non-signer in onlySigner method');
                  _;
                }
                /**
                 * Modifier that will execute internal code block only if the contract has not been initialized yet
                 */
                modifier onlyUninitialized {
                  require(!initialized, 'Contract already initialized');
                  _;
                }
                /**
                 * Gets called when a transaction is received with data that does not match any other method
                 */
                fallback() external payable {
                  if (msg.value > 0) {
                    // Fire deposited event if we are receiving funds
                    emit Deposited(msg.sender, msg.value, msg.data);
                  }
                }
                /**
                 * Gets called when a transaction is received with ether and no data
                 */
                receive() external payable {
                  if (msg.value > 0) {
                    // Fire deposited event if we are receiving funds
                    // message data is always empty for receive. If there is data it is sent to fallback function.
                    emit Deposited(msg.sender, msg.value, '');
                  }
                }
                /**
                 * Execute a multi-signature transaction from this wallet using 2 signers: one from msg.sender and the other from ecrecover.
                 * Sequence IDs are numbers starting from 1. They are used to prevent replay attacks and may not be repeated.
                 *
                 * @param toAddress the destination address to send an outgoing transaction
                 * @param value the amount in Wei to be sent
                 * @param data the data to send to the toAddress when invoking the transaction
                 * @param expireTime the number of seconds since 1970 for which this transaction is valid
                 * @param sequenceId the unique sequence id obtainable from getNextSequenceId
                 * @param signature see Data Formats
                 */
                function sendMultiSig(
                  address toAddress,
                  uint256 value,
                  bytes calldata data,
                  uint256 expireTime,
                  uint256 sequenceId,
                  bytes calldata signature
                ) external onlySigner {
                  // Verify the other signer
                  bytes32 operationHash = keccak256(
                    abi.encodePacked(
                      getNetworkId(),
                      toAddress,
                      value,
                      data,
                      expireTime,
                      sequenceId
                    )
                  );
                  address otherSigner = verifyMultiSig(
                    toAddress,
                    operationHash,
                    signature,
                    expireTime,
                    sequenceId
                  );
                  // Success, send the transaction
                  (bool success, ) = toAddress.call{ value: value }(data);
                  require(success, 'Call execution failed');
                  emit Transacted(
                    msg.sender,
                    otherSigner,
                    operationHash,
                    toAddress,
                    value,
                    data
                  );
                }
                /**
                 * Execute a batched multi-signature transaction from this wallet using 2 signers: one from msg.sender and the other from ecrecover.
                 * Sequence IDs are numbers starting from 1. They are used to prevent replay attacks and may not be repeated.
                 * The recipients and values to send are encoded in two arrays, where for index i, recipients[i] will be sent values[i].
                 *
                 * @param recipients The list of recipients to send to
                 * @param values The list of values to send to
                 * @param expireTime the number of seconds since 1970 for which this transaction is valid
                 * @param sequenceId the unique sequence id obtainable from getNextSequenceId
                 * @param signature see Data Formats
                 */
                function sendMultiSigBatch(
                  address[] calldata recipients,
                  uint256[] calldata values,
                  uint256 expireTime,
                  uint256 sequenceId,
                  bytes calldata signature
                ) external onlySigner {
                  require(recipients.length != 0, 'Not enough recipients');
                  require(
                    recipients.length == values.length,
                    'Unequal recipients and values'
                  );
                  require(recipients.length < 256, 'Too many recipients, max 255');
                  // Verify the other signer
                  bytes32 operationHash = keccak256(
                    abi.encodePacked(
                      getBatchNetworkId(),
                      recipients,
                      values,
                      expireTime,
                      sequenceId
                    )
                  );
                  // the first parameter (toAddress) is used to ensure transactions in safe mode only go to a signer
                  // if in safe mode, we should use normal sendMultiSig to recover, so this check will always fail if in safe mode
                  require(!safeMode, 'Batch in safe mode');
                  address otherSigner = verifyMultiSig(
                    address(0x0),
                    operationHash,
                    signature,
                    expireTime,
                    sequenceId
                  );
                  batchTransfer(recipients, values);
                  emit BatchTransacted(msg.sender, otherSigner, operationHash);
                }
                /**
                 * Transfer funds in a batch to each of recipients
                 * @param recipients The list of recipients to send to
                 * @param values The list of values to send to recipients.
                 *  The recipient with index i in recipients array will be sent values[i].
                 *  Thus, recipients and values must be the same length
                 */
                function batchTransfer(
                  address[] calldata recipients,
                  uint256[] calldata values
                ) internal {
                  for (uint256 i = 0; i < recipients.length; i++) {
                    require(address(this).balance >= values[i], 'Insufficient funds');
                    (bool success, ) = recipients[i].call{ value: values[i] }('');
                    require(success, 'Call failed');
                    emit BatchTransfer(msg.sender, recipients[i], values[i]);
                  }
                }
                /**
                 * Execute a multi-signature token transfer from this wallet using 2 signers: one from msg.sender and the other from ecrecover.
                 * Sequence IDs are numbers starting from 1. They are used to prevent replay attacks and may not be repeated.
                 *
                 * @param toAddress the destination address to send an outgoing transaction
                 * @param value the amount in tokens to be sent
                 * @param tokenContractAddress the address of the erc20 token contract
                 * @param expireTime the number of seconds since 1970 for which this transaction is valid
                 * @param sequenceId the unique sequence id obtainable from getNextSequenceId
                 * @param signature see Data Formats
                 */
                function sendMultiSigToken(
                  address toAddress,
                  uint256 value,
                  address tokenContractAddress,
                  uint256 expireTime,
                  uint256 sequenceId,
                  bytes calldata signature
                ) external onlySigner {
                  // Verify the other signer
                  bytes32 operationHash = keccak256(
                    abi.encodePacked(
                      getTokenNetworkId(),
                      toAddress,
                      value,
                      tokenContractAddress,
                      expireTime,
                      sequenceId
                    )
                  );
                  verifyMultiSig(toAddress, operationHash, signature, expireTime, sequenceId);
                  TransferHelper.safeTransfer(tokenContractAddress, toAddress, value);
                }
                /**
                 * Execute a token flush from one of the forwarder addresses. This transfer needs only a single signature and can be done by any signer
                 *
                 * @param forwarderAddress the address of the forwarder address to flush the tokens from
                 * @param tokenContractAddress the address of the erc20 token contract
                 */
                function flushForwarderTokens(
                  address payable forwarderAddress,
                  address tokenContractAddress
                ) external onlySigner {
                  IForwarder forwarder = IForwarder(forwarderAddress);
                  forwarder.flushTokens(tokenContractAddress);
                }
                /**
                 * Execute a ERC721 token flush from one of the forwarder addresses. This transfer needs only a single signature and can be done by any signer
                 *
                 * @param forwarderAddress the address of the forwarder address to flush the tokens from
                 * @param tokenContractAddress the address of the erc20 token contract
                 */
                function flushERC721ForwarderTokens(
                  address payable forwarderAddress,
                  address tokenContractAddress,
                  uint256 tokenId
                ) external onlySigner {
                  IForwarder forwarder = IForwarder(forwarderAddress);
                  forwarder.flushERC721Token(tokenContractAddress, tokenId);
                }
                /**
                 * Execute a ERC1155 batch token flush from one of the forwarder addresses.
                 * This transfer needs only a single signature and can be done by any signer.
                 *
                 * @param forwarderAddress the address of the forwarder address to flush the tokens from
                 * @param tokenContractAddress the address of the erc1155 token contract
                 */
                function batchFlushERC1155ForwarderTokens(
                  address payable forwarderAddress,
                  address tokenContractAddress,
                  uint256[] calldata tokenIds
                ) external onlySigner {
                  IForwarder forwarder = IForwarder(forwarderAddress);
                  forwarder.batchFlushERC1155Tokens(tokenContractAddress, tokenIds);
                }
                /**
                 * Execute a ERC1155 token flush from one of the forwarder addresses.
                 * This transfer needs only a single signature and can be done by any signer.
                 *
                 * @param forwarderAddress the address of the forwarder address to flush the tokens from
                 * @param tokenContractAddress the address of the erc1155 token contract
                 * @param tokenId the token id associated with the ERC1155
                 */
                function flushERC1155ForwarderTokens(
                  address payable forwarderAddress,
                  address tokenContractAddress,
                  uint256 tokenId
                ) external onlySigner {
                  IForwarder forwarder = IForwarder(forwarderAddress);
                  forwarder.flushERC1155Tokens(tokenContractAddress, tokenId);
                }
                /**
                 * Sets the autoflush 721 parameter on the forwarder.
                 *
                 * @param forwarderAddress the address of the forwarder to toggle.
                 * @param autoFlush whether to autoflush erc721 tokens
                 */
                function setAutoFlush721(address forwarderAddress, bool autoFlush)
                  external
                  onlySigner
                {
                  IForwarder forwarder = IForwarder(forwarderAddress);
                  forwarder.setAutoFlush721(autoFlush);
                }
                /**
                 * Sets the autoflush 721 parameter on the forwarder.
                 *
                 * @param forwarderAddress the address of the forwarder to toggle.
                 * @param autoFlush whether to autoflush erc1155 tokens
                 */
                function setAutoFlush1155(address forwarderAddress, bool autoFlush)
                  external
                  onlySigner
                {
                  IForwarder forwarder = IForwarder(forwarderAddress);
                  forwarder.setAutoFlush1155(autoFlush);
                }
                /**
                 * Do common multisig verification for both eth sends and erc20token transfers
                 *
                 * @param toAddress the destination address to send an outgoing transaction
                 * @param operationHash see Data Formats
                 * @param signature see Data Formats
                 * @param expireTime the number of seconds since 1970 for which this transaction is valid
                 * @param sequenceId the unique sequence id obtainable from getNextSequenceId
                 * returns address that has created the signature
                 */
                function verifyMultiSig(
                  address toAddress,
                  bytes32 operationHash,
                  bytes calldata signature,
                  uint256 expireTime,
                  uint256 sequenceId
                ) private returns (address) {
                  address otherSigner = recoverAddressFromSignature(operationHash, signature);
                  // Verify if we are in safe mode. In safe mode, the wallet can only send to signers
                  require(!safeMode || isSigner(toAddress), 'External transfer in safe mode');
                  // Verify that the transaction has not expired
                  require(expireTime >= block.timestamp, 'Transaction expired');
                  // Try to insert the sequence ID. Will revert if the sequence id was invalid
                  tryInsertSequenceId(sequenceId);
                  require(isSigner(otherSigner), 'Invalid signer');
                  require(otherSigner != msg.sender, 'Signers cannot be equal');
                  return otherSigner;
                }
                /**
                 * ERC721 standard callback function for when a ERC721 is transfered.
                 *
                 * @param _operator The address of the nft contract
                 * @param _from The address of the sender
                 * @param _tokenId The token id of the nft
                 * @param _data Additional data with no specified format, sent in call to `_to`
                 */
                function onERC721Received(
                  address _operator,
                  address _from,
                  uint256 _tokenId,
                  bytes memory _data
                ) external virtual override returns (bytes4) {
                  return this.onERC721Received.selector;
                }
                /**
                 * @inheritdoc IERC1155Receiver
                 */
                function onERC1155Received(
                  address _operator,
                  address _from,
                  uint256 id,
                  uint256 value,
                  bytes calldata data
                ) external virtual override returns (bytes4) {
                  return this.onERC1155Received.selector;
                }
                /**
                 * @inheritdoc IERC1155Receiver
                 */
                function onERC1155BatchReceived(
                  address _operator,
                  address _from,
                  uint256[] calldata ids,
                  uint256[] calldata values,
                  bytes calldata data
                ) external virtual override returns (bytes4) {
                  return this.onERC1155BatchReceived.selector;
                }
                /**
                 * Irrevocably puts contract into safe mode. When in this mode, transactions may only be sent to signing addresses.
                 */
                function activateSafeMode() external onlySigner {
                  safeMode = true;
                  emit SafeModeActivated(msg.sender);
                }
                /**
                 * Gets signer's address using ecrecover
                 * @param operationHash see Data Formats
                 * @param signature see Data Formats
                 * returns address recovered from the signature
                 */
                function recoverAddressFromSignature(
                  bytes32 operationHash,
                  bytes memory signature
                ) private pure returns (address) {
                  require(signature.length == 65, 'Invalid signature - wrong length');
                  // We need to unpack the signature, which is given as an array of 65 bytes (like eth.sign)
                  bytes32 r;
                  bytes32 s;
                  uint8 v;
                  // solhint-disable-next-line
                  assembly {
                    r := mload(add(signature, 32))
                    s := mload(add(signature, 64))
                    v := and(mload(add(signature, 65)), 255)
                  }
                  if (v < 27) {
                    v += 27; // Ethereum versions are 27 or 28 as opposed to 0 or 1 which is submitted by some signing libs
                  }
                  // protect against signature malleability
                  // S value must be in the lower half orader
                  // reference: https://github.com/OpenZeppelin/openzeppelin-contracts/blob/051d340171a93a3d401aaaea46b4b62fa81e5d7c/contracts/cryptography/ECDSA.sol#L53
                  require(
                    uint256(s) <=
                      0x7FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF5D576E7357A4501DDFE92F46681B20A0,
                    "ECDSA: invalid signature 's' value"
                  );
                  // note that this returns 0 if the signature is invalid
                  // Since 0x0 can never be a signer, when the recovered signer address
                  // is checked against our signer list, that 0x0 will cause an invalid signer failure
                  return ecrecover(operationHash, v, r, s);
                }
                /**
                 * Verify that the sequence id has not been used before and inserts it. Throws if the sequence ID was not accepted.
                 * We collect a window of up to 10 recent sequence ids, and allow any sequence id that is not in the window and
                 * greater than the minimum element in the window.
                 * @param sequenceId to insert into array of stored ids
                 */
                function tryInsertSequenceId(uint256 sequenceId) private onlySigner {
                  // Keep a pointer to the lowest value element in the window
                  uint256 lowestValueIndex = 0;
                  // fetch recentSequenceIds into memory for function context to avoid unnecessary sloads
                    uint256[SEQUENCE_ID_WINDOW_SIZE] memory _recentSequenceIds
                   = recentSequenceIds;
                  for (uint256 i = 0; i < SEQUENCE_ID_WINDOW_SIZE; i++) {
                    require(_recentSequenceIds[i] != sequenceId, 'Sequence ID already used');
                    if (_recentSequenceIds[i] < _recentSequenceIds[lowestValueIndex]) {
                      lowestValueIndex = i;
                    }
                  }
                  // The sequence ID being used is lower than the lowest value in the window
                  // so we cannot accept it as it may have been used before
                  require(
                    sequenceId > _recentSequenceIds[lowestValueIndex],
                    'Sequence ID below window'
                  );
                  // Block sequence IDs which are much higher than the lowest value
                  // This prevents people blocking the contract by using very large sequence IDs quickly
                  require(
                    sequenceId <=
                      (_recentSequenceIds[lowestValueIndex] + MAX_SEQUENCE_ID_INCREASE),
                    'Sequence ID above maximum'
                  );
                  recentSequenceIds[lowestValueIndex] = sequenceId;
                }
                /**
                 * Gets the next available sequence ID for signing when using executeAndConfirm
                 * returns the sequenceId one higher than the highest currently stored
                 */
                function getNextSequenceId() external view returns (uint256) {
                  uint256 highestSequenceId = 0;
                  for (uint256 i = 0; i < SEQUENCE_ID_WINDOW_SIZE; i++) {
                    if (recentSequenceIds[i] > highestSequenceId) {
                      highestSequenceId = recentSequenceIds[i];
                    }
                  }
                  return highestSequenceId + 1;
                }
              }
              // SPDX-License-Identifier: GPL-3.0-or-later
              // source: https://github.com/Uniswap/solidity-lib/blob/master/contracts/libraries/TransferHelper.sol
              pragma solidity 0.8.10;
              import '@openzeppelin/contracts/utils/Address.sol';
              // helper methods for interacting with ERC20 tokens and sending ETH that do not consistently return true/false
              library TransferHelper {
                function safeTransfer(
                  address token,
                  address to,
                  uint256 value
                ) internal {
                  // bytes4(keccak256(bytes('transfer(address,uint256)')));
                  (bool success, bytes memory data) = token.call(
                    abi.encodeWithSelector(0xa9059cbb, to, value)
                  );
                  require(
                    success && (data.length == 0 || abi.decode(data, (bool))),
                    'TransferHelper::safeTransfer: transfer failed'
                  );
                }
                function safeTransferFrom(
                  address token,
                  address from,
                  address to,
                  uint256 value
                ) internal {
                  // bytes4(keccak256(bytes('transferFrom(address,address,uint256)')));
                  (bool success, bytes memory returndata) = token.call(
                    abi.encodeWithSelector(0x23b872dd, from, to, value)
                  );
                  Address.verifyCallResult(
                    success,
                    returndata,
                    'TransferHelper::transferFrom: transferFrom failed'
                  );
                }
              }
              // SPDX-License-Identifier: UNLICENSED
              pragma solidity 0.8.10;
              /**
               * Contract that exposes the needed erc20 token functions
               */
              abstract contract ERC20Interface {
                // Send _value amount of tokens to address _to
                function transfer(address _to, uint256 _value)
                  public
                  virtual
                  returns (bool success);
                // Get the account balance of another account with address _owner
                function balanceOf(address _owner)
                  public
                  virtual
                  view
                  returns (uint256 balance);
              }
              pragma solidity ^0.8.0;
              import '@openzeppelin/contracts/utils/introspection/IERC165.sol';
              interface IForwarder is IERC165 {
                /**
                 * Sets the autoflush721 parameter.
                 *
                 * @param autoFlush whether to autoflush erc721 tokens
                 */
                function setAutoFlush721(bool autoFlush) external;
                /**
                 * Sets the autoflush1155 parameter.
                 *
                 * @param autoFlush whether to autoflush erc1155 tokens
                 */
                function setAutoFlush1155(bool autoFlush) external;
                /**
                 * Execute a token transfer of the full balance from the forwarder token to the parent address
                 *
                 * @param tokenContractAddress the address of the erc20 token contract
                 */
                function flushTokens(address tokenContractAddress) external;
                /**
                 * Execute a nft transfer from the forwarder to the parent address
                 *
                 * @param tokenContractAddress the address of the ERC721 NFT contract
                 * @param tokenId The token id of the nft
                 */
                function flushERC721Token(address tokenContractAddress, uint256 tokenId)
                  external;
                /**
                 * Execute a nft transfer from the forwarder to the parent address.
                 *
                 * @param tokenContractAddress the address of the ERC1155 NFT contract
                 * @param tokenId The token id of the nft
                 */
                function flushERC1155Tokens(address tokenContractAddress, uint256 tokenId)
                  external;
                /**
                 * Execute a batch nft transfer from the forwarder to the parent address.
                 *
                 * @param tokenContractAddress the address of the ERC1155 NFT contract
                 * @param tokenIds The token ids of the nfts
                 */
                function batchFlushERC1155Tokens(
                  address tokenContractAddress,
                  uint256[] calldata tokenIds
                ) external;
              }
              // SPDX-License-Identifier: MIT
              // OpenZeppelin Contracts v4.4.1 (token/ERC721/IERC721Receiver.sol)
              pragma solidity ^0.8.0;
              /**
               * @title ERC721 token receiver interface
               * @dev Interface for any contract that wants to support safeTransfers
               * from ERC721 asset contracts.
               */
              interface IERC721Receiver {
                  /**
                   * @dev Whenever an {IERC721} `tokenId` token is transferred to this contract via {IERC721-safeTransferFrom}
                   * by `operator` from `from`, this function is called.
                   *
                   * It must return its Solidity selector to confirm the token transfer.
                   * If any other value is returned or the interface is not implemented by the recipient, the transfer will be reverted.
                   *
                   * The selector can be obtained in Solidity with `IERC721.onERC721Received.selector`.
                   */
                  function onERC721Received(
                      address operator,
                      address from,
                      uint256 tokenId,
                      bytes calldata data
                  ) external returns (bytes4);
              }
              // SPDX-License-Identifier: MIT
              // OpenZeppelin Contracts v4.4.1 (token/ERC1155/utils/ERC1155Receiver.sol)
              pragma solidity ^0.8.0;
              import "../IERC1155Receiver.sol";
              import "../../../utils/introspection/ERC165.sol";
              /**
               * @dev _Available since v3.1._
               */
              abstract contract ERC1155Receiver is ERC165, IERC1155Receiver {
                  /**
                   * @dev See {IERC165-supportsInterface}.
                   */
                  function supportsInterface(bytes4 interfaceId) public view virtual override(ERC165, IERC165) returns (bool) {
                      return interfaceId == type(IERC1155Receiver).interfaceId || super.supportsInterface(interfaceId);
                  }
              }
              // SPDX-License-Identifier: MIT
              // OpenZeppelin Contracts v4.4.1 (utils/Address.sol)
              pragma solidity ^0.8.0;
              /**
               * @dev Collection of functions related to the address type
               */
              library Address {
                  /**
                   * @dev Returns true if `account` is a contract.
                   *
                   * [IMPORTANT]
                   * ====
                   * It is unsafe to assume that an address for which this function returns
                   * false is an externally-owned account (EOA) and not a contract.
                   *
                   * Among others, `isContract` will return false for the following
                   * types of addresses:
                   *
                   *  - an externally-owned account
                   *  - a contract in construction
                   *  - an address where a contract will be created
                   *  - an address where a contract lived, but was destroyed
                   * ====
                   */
                  function isContract(address account) internal view returns (bool) {
                      // This method relies on extcodesize, which returns 0 for contracts in
                      // construction, since the code is only stored at the end of the
                      // constructor execution.
                      uint256 size;
                      assembly {
                          size := extcodesize(account)
                      }
                      return size > 0;
                  }
                  /**
                   * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
                   * `recipient`, forwarding all available gas and reverting on errors.
                   *
                   * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
                   * of certain opcodes, possibly making contracts go over the 2300 gas limit
                   * imposed by `transfer`, making them unable to receive funds via
                   * `transfer`. {sendValue} removes this limitation.
                   *
                   * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
                   *
                   * IMPORTANT: because control is transferred to `recipient`, care must be
                   * taken to not create reentrancy vulnerabilities. Consider using
                   * {ReentrancyGuard} or the
                   * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
                   */
                  function sendValue(address payable recipient, uint256 amount) internal {
                      require(address(this).balance >= amount, "Address: insufficient balance");
                      (bool success, ) = recipient.call{value: amount}("");
                      require(success, "Address: unable to send value, recipient may have reverted");
                  }
                  /**
                   * @dev Performs a Solidity function call using a low level `call`. A
                   * plain `call` is an unsafe replacement for a function call: use this
                   * function instead.
                   *
                   * If `target` reverts with a revert reason, it is bubbled up by this
                   * function (like regular Solidity function calls).
                   *
                   * Returns the raw returned data. To convert to the expected return value,
                   * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
                   *
                   * Requirements:
                   *
                   * - `target` must be a contract.
                   * - calling `target` with `data` must not revert.
                   *
                   * _Available since v3.1._
                   */
                  function functionCall(address target, bytes memory data) internal returns (bytes memory) {
                      return functionCall(target, data, "Address: low-level call failed");
                  }
                  /**
                   * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
                   * `errorMessage` as a fallback revert reason when `target` reverts.
                   *
                   * _Available since v3.1._
                   */
                  function functionCall(
                      address target,
                      bytes memory data,
                      string memory errorMessage
                  ) internal returns (bytes memory) {
                      return functionCallWithValue(target, data, 0, errorMessage);
                  }
                  /**
                   * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
                   * but also transferring `value` wei to `target`.
                   *
                   * Requirements:
                   *
                   * - the calling contract must have an ETH balance of at least `value`.
                   * - the called Solidity function must be `payable`.
                   *
                   * _Available since v3.1._
                   */
                  function functionCallWithValue(
                      address target,
                      bytes memory data,
                      uint256 value
                  ) internal returns (bytes memory) {
                      return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
                  }
                  /**
                   * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
                   * with `errorMessage` as a fallback revert reason when `target` reverts.
                   *
                   * _Available since v3.1._
                   */
                  function functionCallWithValue(
                      address target,
                      bytes memory data,
                      uint256 value,
                      string memory errorMessage
                  ) internal returns (bytes memory) {
                      require(address(this).balance >= value, "Address: insufficient balance for call");
                      require(isContract(target), "Address: call to non-contract");
                      (bool success, bytes memory returndata) = target.call{value: value}(data);
                      return verifyCallResult(success, returndata, errorMessage);
                  }
                  /**
                   * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
                   * but performing a static call.
                   *
                   * _Available since v3.3._
                   */
                  function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
                      return functionStaticCall(target, data, "Address: low-level static call failed");
                  }
                  /**
                   * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
                   * but performing a static call.
                   *
                   * _Available since v3.3._
                   */
                  function functionStaticCall(
                      address target,
                      bytes memory data,
                      string memory errorMessage
                  ) internal view returns (bytes memory) {
                      require(isContract(target), "Address: static call to non-contract");
                      (bool success, bytes memory returndata) = target.staticcall(data);
                      return verifyCallResult(success, returndata, errorMessage);
                  }
                  /**
                   * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
                   * but performing a delegate call.
                   *
                   * _Available since v3.4._
                   */
                  function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {
                      return functionDelegateCall(target, data, "Address: low-level delegate call failed");
                  }
                  /**
                   * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
                   * but performing a delegate call.
                   *
                   * _Available since v3.4._
                   */
                  function functionDelegateCall(
                      address target,
                      bytes memory data,
                      string memory errorMessage
                  ) internal returns (bytes memory) {
                      require(isContract(target), "Address: delegate call to non-contract");
                      (bool success, bytes memory returndata) = target.delegatecall(data);
                      return verifyCallResult(success, returndata, errorMessage);
                  }
                  /**
                   * @dev Tool to verifies that a low level call was successful, and revert if it wasn't, either by bubbling the
                   * revert reason using the provided one.
                   *
                   * _Available since v4.3._
                   */
                  function verifyCallResult(
                      bool success,
                      bytes memory returndata,
                      string memory errorMessage
                  ) internal pure returns (bytes memory) {
                      if (success) {
                          return returndata;
                      } else {
                          // Look for revert reason and bubble it up if present
                          if (returndata.length > 0) {
                              // The easiest way to bubble the revert reason is using memory via assembly
                              assembly {
                                  let returndata_size := mload(returndata)
                                  revert(add(32, returndata), returndata_size)
                              }
                          } else {
                              revert(errorMessage);
                          }
                      }
                  }
              }
              // SPDX-License-Identifier: MIT
              // OpenZeppelin Contracts v4.4.1 (utils/introspection/IERC165.sol)
              pragma solidity ^0.8.0;
              /**
               * @dev Interface of the ERC165 standard, as defined in the
               * https://eips.ethereum.org/EIPS/eip-165[EIP].
               *
               * Implementers can declare support of contract interfaces, which can then be
               * queried by others ({ERC165Checker}).
               *
               * For an implementation, see {ERC165}.
               */
              interface IERC165 {
                  /**
                   * @dev Returns true if this contract implements the interface defined by
                   * `interfaceId`. See the corresponding
                   * https://eips.ethereum.org/EIPS/eip-165#how-interfaces-are-identified[EIP section]
                   * to learn more about how these ids are created.
                   *
                   * This function call must use less than 30 000 gas.
                   */
                  function supportsInterface(bytes4 interfaceId) external view returns (bool);
              }
              // SPDX-License-Identifier: MIT
              // OpenZeppelin Contracts v4.4.1 (token/ERC1155/IERC1155Receiver.sol)
              pragma solidity ^0.8.0;
              import "../../utils/introspection/IERC165.sol";
              /**
               * @dev _Available since v3.1._
               */
              interface IERC1155Receiver is IERC165 {
                  /**
                      @dev Handles the receipt of a single ERC1155 token type. This function is
                      called at the end of a `safeTransferFrom` after the balance has been updated.
                      To accept the transfer, this must return
                      `bytes4(keccak256("onERC1155Received(address,address,uint256,uint256,bytes)"))`
                      (i.e. 0xf23a6e61, or its own function selector).
                      @param operator The address which initiated the transfer (i.e. msg.sender)
                      @param from The address which previously owned the token
                      @param id The ID of the token being transferred
                      @param value The amount of tokens being transferred
                      @param data Additional data with no specified format
                      @return `bytes4(keccak256("onERC1155Received(address,address,uint256,uint256,bytes)"))` if transfer is allowed
                  */
                  function onERC1155Received(
                      address operator,
                      address from,
                      uint256 id,
                      uint256 value,
                      bytes calldata data
                  ) external returns (bytes4);
                  /**
                      @dev Handles the receipt of a multiple ERC1155 token types. This function
                      is called at the end of a `safeBatchTransferFrom` after the balances have
                      been updated. To accept the transfer(s), this must return
                      `bytes4(keccak256("onERC1155BatchReceived(address,address,uint256[],uint256[],bytes)"))`
                      (i.e. 0xbc197c81, or its own function selector).
                      @param operator The address which initiated the batch transfer (i.e. msg.sender)
                      @param from The address which previously owned the token
                      @param ids An array containing ids of each token being transferred (order and length must match values array)
                      @param values An array containing amounts of each token being transferred (order and length must match ids array)
                      @param data Additional data with no specified format
                      @return `bytes4(keccak256("onERC1155BatchReceived(address,address,uint256[],uint256[],bytes)"))` if transfer is allowed
                  */
                  function onERC1155BatchReceived(
                      address operator,
                      address from,
                      uint256[] calldata ids,
                      uint256[] calldata values,
                      bytes calldata data
                  ) external returns (bytes4);
              }
              // SPDX-License-Identifier: MIT
              // OpenZeppelin Contracts v4.4.1 (utils/introspection/ERC165.sol)
              pragma solidity ^0.8.0;
              import "./IERC165.sol";
              /**
               * @dev Implementation of the {IERC165} interface.
               *
               * Contracts that want to implement ERC165 should inherit from this contract and override {supportsInterface} to check
               * for the additional interface id that will be supported. For example:
               *
               * ```solidity
               * function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
               *     return interfaceId == type(MyInterface).interfaceId || super.supportsInterface(interfaceId);
               * }
               * ```
               *
               * Alternatively, {ERC165Storage} provides an easier to use but more expensive implementation.
               */
              abstract contract ERC165 is IERC165 {
                  /**
                   * @dev See {IERC165-supportsInterface}.
                   */
                  function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
                      return interfaceId == type(IERC165).interfaceId;
                  }
              }
              

              File 4 of 5: Forwarder
              // SPDX-License-Identifier: Apache-2.0
              pragma solidity 0.8.10;
              import '@openzeppelin/contracts/token/ERC1155/IERC1155.sol';
              import '@openzeppelin/contracts/token/ERC721/IERC721.sol';
              import '@openzeppelin/contracts/token/ERC721/IERC721Receiver.sol';
              import '@openzeppelin/contracts/token/ERC1155/utils/ERC1155Receiver.sol';
              import './ERC20Interface.sol';
              import './TransferHelper.sol';
              import './IForwarder.sol';
              /**
               * Contract that will forward any incoming Ether to the creator of the contract
               *
               */
              contract Forwarder is IERC721Receiver, ERC1155Receiver, IForwarder {
                // Address to which any funds sent to this contract will be forwarded
                address public parentAddress;
                bool public autoFlush721 = true;
                bool public autoFlush1155 = true;
                event ForwarderDeposited(address from, uint256 value, bytes data);
                /**
                 * Initialize the contract, and sets the destination address to that of the creator
                 */
                function init(
                  address _parentAddress,
                  bool _autoFlush721,
                  bool _autoFlush1155
                ) external onlyUninitialized {
                  parentAddress = _parentAddress;
                  uint256 value = address(this).balance;
                  // set whether we want to automatically flush erc721/erc1155 tokens or not
                  autoFlush721 = _autoFlush721;
                  autoFlush1155 = _autoFlush1155;
                  if (value == 0) {
                    return;
                  }
                  (bool success, ) = parentAddress.call{ value: value }('');
                  require(success, 'Flush failed');
                  // NOTE: since we are forwarding on initialization,
                  // we don't have the context of the original sender.
                  // We still emit an event about the forwarding but set
                  // the sender to the forwarder itself
                  emit ForwarderDeposited(address(this), value, msg.data);
                }
                /**
                 * Modifier that will execute internal code block only if the sender is the parent address
                 */
                modifier onlyParent {
                  require(msg.sender == parentAddress, 'Only Parent');
                  _;
                }
                /**
                 * Modifier that will execute internal code block only if the contract has not been initialized yet
                 */
                modifier onlyUninitialized {
                  require(parentAddress == address(0x0), 'Already initialized');
                  _;
                }
                /**
                 * Default function; Gets called when data is sent but does not match any other function
                 */
                fallback() external payable {
                  flush();
                }
                /**
                 * Default function; Gets called when Ether is deposited with no data, and forwards it to the parent address
                 */
                receive() external payable {
                  flush();
                }
                /**
                 * @inheritdoc IForwarder
                 */
                function setAutoFlush721(bool autoFlush)
                  external
                  virtual
                  override
                  onlyParent
                {
                  autoFlush721 = autoFlush;
                }
                /**
                 * @inheritdoc IForwarder
                 */
                function setAutoFlush1155(bool autoFlush)
                  external
                  virtual
                  override
                  onlyParent
                {
                  autoFlush1155 = autoFlush;
                }
                /**
                 * ERC721 standard callback function for when a ERC721 is transfered. The forwarder will send the nft
                 * to the base wallet once the nft contract invokes this method after transfering the nft.
                 *
                 * @param _operator The address which called `safeTransferFrom` function
                 * @param _from The address of the sender
                 * @param _tokenId The token id of the nft
                 * @param data Additional data with no specified format, sent in call to `_to`
                 */
                function onERC721Received(
                  address _operator,
                  address _from,
                  uint256 _tokenId,
                  bytes memory data
                ) external virtual override returns (bytes4) {
                  if (autoFlush721) {
                    IERC721 instance = IERC721(msg.sender);
                    require(
                      instance.supportsInterface(type(IERC721).interfaceId),
                      'The caller does not support the ERC721 interface'
                    );
                    // this won't work for ERC721 re-entrancy
                    instance.safeTransferFrom(address(this), parentAddress, _tokenId, data);
                  }
                  return this.onERC721Received.selector;
                }
                function callFromParent(
                  address target,
                  uint256 value,
                  bytes calldata data
                ) external onlyParent returns (bytes memory) {
                  (bool success, bytes memory returnedData) = target.call{ value: value }(
                    data
                  );
                  require(success, 'Parent call execution failed');
                  return returnedData;
                }
                /**
                 * @inheritdoc IERC1155Receiver
                 */
                function onERC1155Received(
                  address _operator,
                  address _from,
                  uint256 id,
                  uint256 value,
                  bytes calldata data
                ) external virtual override returns (bytes4) {
                  IERC1155 instance = IERC1155(msg.sender);
                  require(
                    instance.supportsInterface(type(IERC1155).interfaceId),
                    'The caller does not support the IERC1155 interface'
                  );
                  if (autoFlush1155) {
                    instance.safeTransferFrom(address(this), parentAddress, id, value, data);
                  }
                  return this.onERC1155Received.selector;
                }
                /**
                 * @inheritdoc IERC1155Receiver
                 */
                function onERC1155BatchReceived(
                  address _operator,
                  address _from,
                  uint256[] calldata ids,
                  uint256[] calldata values,
                  bytes calldata data
                ) external virtual override returns (bytes4) {
                  IERC1155 instance = IERC1155(msg.sender);
                  require(
                    instance.supportsInterface(type(IERC1155).interfaceId),
                    'The caller does not support the IERC1155 interface'
                  );
                  if (autoFlush1155) {
                    instance.safeBatchTransferFrom(
                      address(this),
                      parentAddress,
                      ids,
                      values,
                      data
                    );
                  }
                  return this.onERC1155BatchReceived.selector;
                }
                /**
                 * @inheritdoc IForwarder
                 */
                function flushTokens(address tokenContractAddress)
                  external
                  virtual
                  override
                  onlyParent
                {
                  ERC20Interface instance = ERC20Interface(tokenContractAddress);
                  address forwarderAddress = address(this);
                  uint256 forwarderBalance = instance.balanceOf(forwarderAddress);
                  if (forwarderBalance == 0) {
                    return;
                  }
                  TransferHelper.safeTransfer(
                    tokenContractAddress,
                    parentAddress,
                    forwarderBalance
                  );
                }
                /**
                 * @inheritdoc IForwarder
                 */
                function flushERC721Token(address tokenContractAddress, uint256 tokenId)
                  external
                  virtual
                  override
                  onlyParent
                {
                  IERC721 instance = IERC721(tokenContractAddress);
                  require(
                    instance.supportsInterface(type(IERC721).interfaceId),
                    'The tokenContractAddress does not support the ERC721 interface'
                  );
                  address ownerAddress = instance.ownerOf(tokenId);
                  instance.transferFrom(ownerAddress, parentAddress, tokenId);
                }
                /**
                 * @inheritdoc IForwarder
                 */
                function flushERC1155Tokens(address tokenContractAddress, uint256 tokenId)
                  external
                  virtual
                  override
                  onlyParent
                {
                  IERC1155 instance = IERC1155(tokenContractAddress);
                  require(
                    instance.supportsInterface(type(IERC1155).interfaceId),
                    'The caller does not support the IERC1155 interface'
                  );
                  address forwarderAddress = address(this);
                  uint256 forwarderBalance = instance.balanceOf(forwarderAddress, tokenId);
                  instance.safeTransferFrom(
                    forwarderAddress,
                    parentAddress,
                    tokenId,
                    forwarderBalance,
                    ''
                  );
                }
                /**
                 * @inheritdoc IForwarder
                 */
                function batchFlushERC1155Tokens(
                  address tokenContractAddress,
                  uint256[] calldata tokenIds
                ) external virtual override onlyParent {
                  IERC1155 instance = IERC1155(tokenContractAddress);
                  require(
                    instance.supportsInterface(type(IERC1155).interfaceId),
                    'The caller does not support the IERC1155 interface'
                  );
                  address forwarderAddress = address(this);
                  uint256[] memory amounts = new uint256[](tokenIds.length);
                  for (uint256 i = 0; i < tokenIds.length; i++) {
                    amounts[i] = instance.balanceOf(forwarderAddress, tokenIds[i]);
                  }
                  instance.safeBatchTransferFrom(
                    forwarderAddress,
                    parentAddress,
                    tokenIds,
                    amounts,
                    ''
                  );
                }
                /**
                 * Flush the entire balance of the contract to the parent address.
                 */
                function flush() public {
                  uint256 value = address(this).balance;
                  if (value == 0) {
                    return;
                  }
                  (bool success, ) = parentAddress.call{ value: value }('');
                  require(success, 'Flush failed');
                  emit ForwarderDeposited(msg.sender, value, msg.data);
                }
                /**
                 * @inheritdoc IERC165
                 */
                function supportsInterface(bytes4 interfaceId)
                  public
                  virtual
                  override(ERC1155Receiver, IERC165)
                  view
                  returns (bool)
                {
                  return
                    interfaceId == type(IForwarder).interfaceId ||
                    super.supportsInterface(interfaceId);
                }
              }
              // SPDX-License-Identifier: MIT
              // OpenZeppelin Contracts v4.4.1 (token/ERC1155/IERC1155.sol)
              pragma solidity ^0.8.0;
              import "../../utils/introspection/IERC165.sol";
              /**
               * @dev Required interface of an ERC1155 compliant contract, as defined in the
               * https://eips.ethereum.org/EIPS/eip-1155[EIP].
               *
               * _Available since v3.1._
               */
              interface IERC1155 is IERC165 {
                  /**
                   * @dev Emitted when `value` tokens of token type `id` are transferred from `from` to `to` by `operator`.
                   */
                  event TransferSingle(address indexed operator, address indexed from, address indexed to, uint256 id, uint256 value);
                  /**
                   * @dev Equivalent to multiple {TransferSingle} events, where `operator`, `from` and `to` are the same for all
                   * transfers.
                   */
                  event TransferBatch(
                      address indexed operator,
                      address indexed from,
                      address indexed to,
                      uint256[] ids,
                      uint256[] values
                  );
                  /**
                   * @dev Emitted when `account` grants or revokes permission to `operator` to transfer their tokens, according to
                   * `approved`.
                   */
                  event ApprovalForAll(address indexed account, address indexed operator, bool approved);
                  /**
                   * @dev Emitted when the URI for token type `id` changes to `value`, if it is a non-programmatic URI.
                   *
                   * If an {URI} event was emitted for `id`, the standard
                   * https://eips.ethereum.org/EIPS/eip-1155#metadata-extensions[guarantees] that `value` will equal the value
                   * returned by {IERC1155MetadataURI-uri}.
                   */
                  event URI(string value, uint256 indexed id);
                  /**
                   * @dev Returns the amount of tokens of token type `id` owned by `account`.
                   *
                   * Requirements:
                   *
                   * - `account` cannot be the zero address.
                   */
                  function balanceOf(address account, uint256 id) external view returns (uint256);
                  /**
                   * @dev xref:ROOT:erc1155.adoc#batch-operations[Batched] version of {balanceOf}.
                   *
                   * Requirements:
                   *
                   * - `accounts` and `ids` must have the same length.
                   */
                  function balanceOfBatch(address[] calldata accounts, uint256[] calldata ids)
                      external
                      view
                      returns (uint256[] memory);
                  /**
                   * @dev Grants or revokes permission to `operator` to transfer the caller's tokens, according to `approved`,
                   *
                   * Emits an {ApprovalForAll} event.
                   *
                   * Requirements:
                   *
                   * - `operator` cannot be the caller.
                   */
                  function setApprovalForAll(address operator, bool approved) external;
                  /**
                   * @dev Returns true if `operator` is approved to transfer ``account``'s tokens.
                   *
                   * See {setApprovalForAll}.
                   */
                  function isApprovedForAll(address account, address operator) external view returns (bool);
                  /**
                   * @dev Transfers `amount` tokens of token type `id` from `from` to `to`.
                   *
                   * Emits a {TransferSingle} event.
                   *
                   * Requirements:
                   *
                   * - `to` cannot be the zero address.
                   * - If the caller is not `from`, it must be have been approved to spend ``from``'s tokens via {setApprovalForAll}.
                   * - `from` must have a balance of tokens of type `id` of at least `amount`.
                   * - If `to` refers to a smart contract, it must implement {IERC1155Receiver-onERC1155Received} and return the
                   * acceptance magic value.
                   */
                  function safeTransferFrom(
                      address from,
                      address to,
                      uint256 id,
                      uint256 amount,
                      bytes calldata data
                  ) external;
                  /**
                   * @dev xref:ROOT:erc1155.adoc#batch-operations[Batched] version of {safeTransferFrom}.
                   *
                   * Emits a {TransferBatch} event.
                   *
                   * Requirements:
                   *
                   * - `ids` and `amounts` must have the same length.
                   * - If `to` refers to a smart contract, it must implement {IERC1155Receiver-onERC1155BatchReceived} and return the
                   * acceptance magic value.
                   */
                  function safeBatchTransferFrom(
                      address from,
                      address to,
                      uint256[] calldata ids,
                      uint256[] calldata amounts,
                      bytes calldata data
                  ) external;
              }
              // SPDX-License-Identifier: MIT
              // OpenZeppelin Contracts v4.4.1 (token/ERC721/IERC721.sol)
              pragma solidity ^0.8.0;
              import "../../utils/introspection/IERC165.sol";
              /**
               * @dev Required interface of an ERC721 compliant contract.
               */
              interface IERC721 is IERC165 {
                  /**
                   * @dev Emitted when `tokenId` token is transferred from `from` to `to`.
                   */
                  event Transfer(address indexed from, address indexed to, uint256 indexed tokenId);
                  /**
                   * @dev Emitted when `owner` enables `approved` to manage the `tokenId` token.
                   */
                  event Approval(address indexed owner, address indexed approved, uint256 indexed tokenId);
                  /**
                   * @dev Emitted when `owner` enables or disables (`approved`) `operator` to manage all of its assets.
                   */
                  event ApprovalForAll(address indexed owner, address indexed operator, bool approved);
                  /**
                   * @dev Returns the number of tokens in ``owner``'s account.
                   */
                  function balanceOf(address owner) external view returns (uint256 balance);
                  /**
                   * @dev Returns the owner of the `tokenId` token.
                   *
                   * Requirements:
                   *
                   * - `tokenId` must exist.
                   */
                  function ownerOf(uint256 tokenId) external view returns (address owner);
                  /**
                   * @dev Safely transfers `tokenId` token from `from` to `to`, checking first that contract recipients
                   * are aware of the ERC721 protocol to prevent tokens from being forever locked.
                   *
                   * Requirements:
                   *
                   * - `from` cannot be the zero address.
                   * - `to` cannot be the zero address.
                   * - `tokenId` token must exist and be owned by `from`.
                   * - If the caller is not `from`, it must be have been allowed to move this token by either {approve} or {setApprovalForAll}.
                   * - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.
                   *
                   * Emits a {Transfer} event.
                   */
                  function safeTransferFrom(
                      address from,
                      address to,
                      uint256 tokenId
                  ) external;
                  /**
                   * @dev Transfers `tokenId` token from `from` to `to`.
                   *
                   * WARNING: Usage of this method is discouraged, use {safeTransferFrom} whenever possible.
                   *
                   * Requirements:
                   *
                   * - `from` cannot be the zero address.
                   * - `to` cannot be the zero address.
                   * - `tokenId` token must be owned by `from`.
                   * - If the caller is not `from`, it must be approved to move this token by either {approve} or {setApprovalForAll}.
                   *
                   * Emits a {Transfer} event.
                   */
                  function transferFrom(
                      address from,
                      address to,
                      uint256 tokenId
                  ) external;
                  /**
                   * @dev Gives permission to `to` to transfer `tokenId` token to another account.
                   * The approval is cleared when the token is transferred.
                   *
                   * Only a single account can be approved at a time, so approving the zero address clears previous approvals.
                   *
                   * Requirements:
                   *
                   * - The caller must own the token or be an approved operator.
                   * - `tokenId` must exist.
                   *
                   * Emits an {Approval} event.
                   */
                  function approve(address to, uint256 tokenId) external;
                  /**
                   * @dev Returns the account approved for `tokenId` token.
                   *
                   * Requirements:
                   *
                   * - `tokenId` must exist.
                   */
                  function getApproved(uint256 tokenId) external view returns (address operator);
                  /**
                   * @dev Approve or remove `operator` as an operator for the caller.
                   * Operators can call {transferFrom} or {safeTransferFrom} for any token owned by the caller.
                   *
                   * Requirements:
                   *
                   * - The `operator` cannot be the caller.
                   *
                   * Emits an {ApprovalForAll} event.
                   */
                  function setApprovalForAll(address operator, bool _approved) external;
                  /**
                   * @dev Returns if the `operator` is allowed to manage all of the assets of `owner`.
                   *
                   * See {setApprovalForAll}
                   */
                  function isApprovedForAll(address owner, address operator) external view returns (bool);
                  /**
                   * @dev Safely transfers `tokenId` token from `from` to `to`.
                   *
                   * Requirements:
                   *
                   * - `from` cannot be the zero address.
                   * - `to` cannot be the zero address.
                   * - `tokenId` token must exist and be owned by `from`.
                   * - If the caller is not `from`, it must be approved to move this token by either {approve} or {setApprovalForAll}.
                   * - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.
                   *
                   * Emits a {Transfer} event.
                   */
                  function safeTransferFrom(
                      address from,
                      address to,
                      uint256 tokenId,
                      bytes calldata data
                  ) external;
              }
              // SPDX-License-Identifier: MIT
              // OpenZeppelin Contracts v4.4.1 (token/ERC721/IERC721Receiver.sol)
              pragma solidity ^0.8.0;
              /**
               * @title ERC721 token receiver interface
               * @dev Interface for any contract that wants to support safeTransfers
               * from ERC721 asset contracts.
               */
              interface IERC721Receiver {
                  /**
                   * @dev Whenever an {IERC721} `tokenId` token is transferred to this contract via {IERC721-safeTransferFrom}
                   * by `operator` from `from`, this function is called.
                   *
                   * It must return its Solidity selector to confirm the token transfer.
                   * If any other value is returned or the interface is not implemented by the recipient, the transfer will be reverted.
                   *
                   * The selector can be obtained in Solidity with `IERC721.onERC721Received.selector`.
                   */
                  function onERC721Received(
                      address operator,
                      address from,
                      uint256 tokenId,
                      bytes calldata data
                  ) external returns (bytes4);
              }
              // SPDX-License-Identifier: MIT
              // OpenZeppelin Contracts v4.4.1 (token/ERC1155/utils/ERC1155Receiver.sol)
              pragma solidity ^0.8.0;
              import "../IERC1155Receiver.sol";
              import "../../../utils/introspection/ERC165.sol";
              /**
               * @dev _Available since v3.1._
               */
              abstract contract ERC1155Receiver is ERC165, IERC1155Receiver {
                  /**
                   * @dev See {IERC165-supportsInterface}.
                   */
                  function supportsInterface(bytes4 interfaceId) public view virtual override(ERC165, IERC165) returns (bool) {
                      return interfaceId == type(IERC1155Receiver).interfaceId || super.supportsInterface(interfaceId);
                  }
              }
              // SPDX-License-Identifier: UNLICENSED
              pragma solidity 0.8.10;
              /**
               * Contract that exposes the needed erc20 token functions
               */
              abstract contract ERC20Interface {
                // Send _value amount of tokens to address _to
                function transfer(address _to, uint256 _value)
                  public
                  virtual
                  returns (bool success);
                // Get the account balance of another account with address _owner
                function balanceOf(address _owner)
                  public
                  virtual
                  view
                  returns (uint256 balance);
              }
              // SPDX-License-Identifier: GPL-3.0-or-later
              // source: https://github.com/Uniswap/solidity-lib/blob/master/contracts/libraries/TransferHelper.sol
              pragma solidity 0.8.10;
              import '@openzeppelin/contracts/utils/Address.sol';
              // helper methods for interacting with ERC20 tokens and sending ETH that do not consistently return true/false
              library TransferHelper {
                function safeTransfer(
                  address token,
                  address to,
                  uint256 value
                ) internal {
                  // bytes4(keccak256(bytes('transfer(address,uint256)')));
                  (bool success, bytes memory data) = token.call(
                    abi.encodeWithSelector(0xa9059cbb, to, value)
                  );
                  require(
                    success && (data.length == 0 || abi.decode(data, (bool))),
                    'TransferHelper::safeTransfer: transfer failed'
                  );
                }
                function safeTransferFrom(
                  address token,
                  address from,
                  address to,
                  uint256 value
                ) internal {
                  // bytes4(keccak256(bytes('transferFrom(address,address,uint256)')));
                  (bool success, bytes memory returndata) = token.call(
                    abi.encodeWithSelector(0x23b872dd, from, to, value)
                  );
                  Address.verifyCallResult(
                    success,
                    returndata,
                    'TransferHelper::transferFrom: transferFrom failed'
                  );
                }
              }
              pragma solidity ^0.8.0;
              import '@openzeppelin/contracts/utils/introspection/IERC165.sol';
              interface IForwarder is IERC165 {
                /**
                 * Sets the autoflush721 parameter.
                 *
                 * @param autoFlush whether to autoflush erc721 tokens
                 */
                function setAutoFlush721(bool autoFlush) external;
                /**
                 * Sets the autoflush1155 parameter.
                 *
                 * @param autoFlush whether to autoflush erc1155 tokens
                 */
                function setAutoFlush1155(bool autoFlush) external;
                /**
                 * Execute a token transfer of the full balance from the forwarder token to the parent address
                 *
                 * @param tokenContractAddress the address of the erc20 token contract
                 */
                function flushTokens(address tokenContractAddress) external;
                /**
                 * Execute a nft transfer from the forwarder to the parent address
                 *
                 * @param tokenContractAddress the address of the ERC721 NFT contract
                 * @param tokenId The token id of the nft
                 */
                function flushERC721Token(address tokenContractAddress, uint256 tokenId)
                  external;
                /**
                 * Execute a nft transfer from the forwarder to the parent address.
                 *
                 * @param tokenContractAddress the address of the ERC1155 NFT contract
                 * @param tokenId The token id of the nft
                 */
                function flushERC1155Tokens(address tokenContractAddress, uint256 tokenId)
                  external;
                /**
                 * Execute a batch nft transfer from the forwarder to the parent address.
                 *
                 * @param tokenContractAddress the address of the ERC1155 NFT contract
                 * @param tokenIds The token ids of the nfts
                 */
                function batchFlushERC1155Tokens(
                  address tokenContractAddress,
                  uint256[] calldata tokenIds
                ) external;
              }
              // SPDX-License-Identifier: MIT
              // OpenZeppelin Contracts v4.4.1 (utils/introspection/IERC165.sol)
              pragma solidity ^0.8.0;
              /**
               * @dev Interface of the ERC165 standard, as defined in the
               * https://eips.ethereum.org/EIPS/eip-165[EIP].
               *
               * Implementers can declare support of contract interfaces, which can then be
               * queried by others ({ERC165Checker}).
               *
               * For an implementation, see {ERC165}.
               */
              interface IERC165 {
                  /**
                   * @dev Returns true if this contract implements the interface defined by
                   * `interfaceId`. See the corresponding
                   * https://eips.ethereum.org/EIPS/eip-165#how-interfaces-are-identified[EIP section]
                   * to learn more about how these ids are created.
                   *
                   * This function call must use less than 30 000 gas.
                   */
                  function supportsInterface(bytes4 interfaceId) external view returns (bool);
              }
              // SPDX-License-Identifier: MIT
              // OpenZeppelin Contracts v4.4.1 (token/ERC1155/IERC1155Receiver.sol)
              pragma solidity ^0.8.0;
              import "../../utils/introspection/IERC165.sol";
              /**
               * @dev _Available since v3.1._
               */
              interface IERC1155Receiver is IERC165 {
                  /**
                      @dev Handles the receipt of a single ERC1155 token type. This function is
                      called at the end of a `safeTransferFrom` after the balance has been updated.
                      To accept the transfer, this must return
                      `bytes4(keccak256("onERC1155Received(address,address,uint256,uint256,bytes)"))`
                      (i.e. 0xf23a6e61, or its own function selector).
                      @param operator The address which initiated the transfer (i.e. msg.sender)
                      @param from The address which previously owned the token
                      @param id The ID of the token being transferred
                      @param value The amount of tokens being transferred
                      @param data Additional data with no specified format
                      @return `bytes4(keccak256("onERC1155Received(address,address,uint256,uint256,bytes)"))` if transfer is allowed
                  */
                  function onERC1155Received(
                      address operator,
                      address from,
                      uint256 id,
                      uint256 value,
                      bytes calldata data
                  ) external returns (bytes4);
                  /**
                      @dev Handles the receipt of a multiple ERC1155 token types. This function
                      is called at the end of a `safeBatchTransferFrom` after the balances have
                      been updated. To accept the transfer(s), this must return
                      `bytes4(keccak256("onERC1155BatchReceived(address,address,uint256[],uint256[],bytes)"))`
                      (i.e. 0xbc197c81, or its own function selector).
                      @param operator The address which initiated the batch transfer (i.e. msg.sender)
                      @param from The address which previously owned the token
                      @param ids An array containing ids of each token being transferred (order and length must match values array)
                      @param values An array containing amounts of each token being transferred (order and length must match ids array)
                      @param data Additional data with no specified format
                      @return `bytes4(keccak256("onERC1155BatchReceived(address,address,uint256[],uint256[],bytes)"))` if transfer is allowed
                  */
                  function onERC1155BatchReceived(
                      address operator,
                      address from,
                      uint256[] calldata ids,
                      uint256[] calldata values,
                      bytes calldata data
                  ) external returns (bytes4);
              }
              // SPDX-License-Identifier: MIT
              // OpenZeppelin Contracts v4.4.1 (utils/introspection/ERC165.sol)
              pragma solidity ^0.8.0;
              import "./IERC165.sol";
              /**
               * @dev Implementation of the {IERC165} interface.
               *
               * Contracts that want to implement ERC165 should inherit from this contract and override {supportsInterface} to check
               * for the additional interface id that will be supported. For example:
               *
               * ```solidity
               * function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
               *     return interfaceId == type(MyInterface).interfaceId || super.supportsInterface(interfaceId);
               * }
               * ```
               *
               * Alternatively, {ERC165Storage} provides an easier to use but more expensive implementation.
               */
              abstract contract ERC165 is IERC165 {
                  /**
                   * @dev See {IERC165-supportsInterface}.
                   */
                  function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
                      return interfaceId == type(IERC165).interfaceId;
                  }
              }
              // SPDX-License-Identifier: MIT
              // OpenZeppelin Contracts v4.4.1 (utils/Address.sol)
              pragma solidity ^0.8.0;
              /**
               * @dev Collection of functions related to the address type
               */
              library Address {
                  /**
                   * @dev Returns true if `account` is a contract.
                   *
                   * [IMPORTANT]
                   * ====
                   * It is unsafe to assume that an address for which this function returns
                   * false is an externally-owned account (EOA) and not a contract.
                   *
                   * Among others, `isContract` will return false for the following
                   * types of addresses:
                   *
                   *  - an externally-owned account
                   *  - a contract in construction
                   *  - an address where a contract will be created
                   *  - an address where a contract lived, but was destroyed
                   * ====
                   */
                  function isContract(address account) internal view returns (bool) {
                      // This method relies on extcodesize, which returns 0 for contracts in
                      // construction, since the code is only stored at the end of the
                      // constructor execution.
                      uint256 size;
                      assembly {
                          size := extcodesize(account)
                      }
                      return size > 0;
                  }
                  /**
                   * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
                   * `recipient`, forwarding all available gas and reverting on errors.
                   *
                   * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
                   * of certain opcodes, possibly making contracts go over the 2300 gas limit
                   * imposed by `transfer`, making them unable to receive funds via
                   * `transfer`. {sendValue} removes this limitation.
                   *
                   * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
                   *
                   * IMPORTANT: because control is transferred to `recipient`, care must be
                   * taken to not create reentrancy vulnerabilities. Consider using
                   * {ReentrancyGuard} or the
                   * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
                   */
                  function sendValue(address payable recipient, uint256 amount) internal {
                      require(address(this).balance >= amount, "Address: insufficient balance");
                      (bool success, ) = recipient.call{value: amount}("");
                      require(success, "Address: unable to send value, recipient may have reverted");
                  }
                  /**
                   * @dev Performs a Solidity function call using a low level `call`. A
                   * plain `call` is an unsafe replacement for a function call: use this
                   * function instead.
                   *
                   * If `target` reverts with a revert reason, it is bubbled up by this
                   * function (like regular Solidity function calls).
                   *
                   * Returns the raw returned data. To convert to the expected return value,
                   * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
                   *
                   * Requirements:
                   *
                   * - `target` must be a contract.
                   * - calling `target` with `data` must not revert.
                   *
                   * _Available since v3.1._
                   */
                  function functionCall(address target, bytes memory data) internal returns (bytes memory) {
                      return functionCall(target, data, "Address: low-level call failed");
                  }
                  /**
                   * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
                   * `errorMessage` as a fallback revert reason when `target` reverts.
                   *
                   * _Available since v3.1._
                   */
                  function functionCall(
                      address target,
                      bytes memory data,
                      string memory errorMessage
                  ) internal returns (bytes memory) {
                      return functionCallWithValue(target, data, 0, errorMessage);
                  }
                  /**
                   * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
                   * but also transferring `value` wei to `target`.
                   *
                   * Requirements:
                   *
                   * - the calling contract must have an ETH balance of at least `value`.
                   * - the called Solidity function must be `payable`.
                   *
                   * _Available since v3.1._
                   */
                  function functionCallWithValue(
                      address target,
                      bytes memory data,
                      uint256 value
                  ) internal returns (bytes memory) {
                      return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
                  }
                  /**
                   * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
                   * with `errorMessage` as a fallback revert reason when `target` reverts.
                   *
                   * _Available since v3.1._
                   */
                  function functionCallWithValue(
                      address target,
                      bytes memory data,
                      uint256 value,
                      string memory errorMessage
                  ) internal returns (bytes memory) {
                      require(address(this).balance >= value, "Address: insufficient balance for call");
                      require(isContract(target), "Address: call to non-contract");
                      (bool success, bytes memory returndata) = target.call{value: value}(data);
                      return verifyCallResult(success, returndata, errorMessage);
                  }
                  /**
                   * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
                   * but performing a static call.
                   *
                   * _Available since v3.3._
                   */
                  function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
                      return functionStaticCall(target, data, "Address: low-level static call failed");
                  }
                  /**
                   * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
                   * but performing a static call.
                   *
                   * _Available since v3.3._
                   */
                  function functionStaticCall(
                      address target,
                      bytes memory data,
                      string memory errorMessage
                  ) internal view returns (bytes memory) {
                      require(isContract(target), "Address: static call to non-contract");
                      (bool success, bytes memory returndata) = target.staticcall(data);
                      return verifyCallResult(success, returndata, errorMessage);
                  }
                  /**
                   * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
                   * but performing a delegate call.
                   *
                   * _Available since v3.4._
                   */
                  function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {
                      return functionDelegateCall(target, data, "Address: low-level delegate call failed");
                  }
                  /**
                   * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
                   * but performing a delegate call.
                   *
                   * _Available since v3.4._
                   */
                  function functionDelegateCall(
                      address target,
                      bytes memory data,
                      string memory errorMessage
                  ) internal returns (bytes memory) {
                      require(isContract(target), "Address: delegate call to non-contract");
                      (bool success, bytes memory returndata) = target.delegatecall(data);
                      return verifyCallResult(success, returndata, errorMessage);
                  }
                  /**
                   * @dev Tool to verifies that a low level call was successful, and revert if it wasn't, either by bubbling the
                   * revert reason using the provided one.
                   *
                   * _Available since v4.3._
                   */
                  function verifyCallResult(
                      bool success,
                      bytes memory returndata,
                      string memory errorMessage
                  ) internal pure returns (bytes memory) {
                      if (success) {
                          return returndata;
                      } else {
                          // Look for revert reason and bubble it up if present
                          if (returndata.length > 0) {
                              // The easiest way to bubble the revert reason is using memory via assembly
                              assembly {
                                  let returndata_size := mload(returndata)
                                  revert(add(32, returndata), returndata_size)
                              }
                          } else {
                              revert(errorMessage);
                          }
                      }
                  }
              }
              

              File 5 of 5: FiatTokenV2_2
              /**
               * SPDX-License-Identifier: Apache-2.0
               *
               * Copyright (c) 2023, Circle Internet Financial, LLC.
               *
               * Licensed under the Apache License, Version 2.0 (the "License");
               * you may not use this file except in compliance with the License.
               * You may obtain a copy of the License at
               *
               * http://www.apache.org/licenses/LICENSE-2.0
               *
               * Unless required by applicable law or agreed to in writing, software
               * distributed under the License is distributed on an "AS IS" BASIS,
               * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
               * See the License for the specific language governing permissions and
               * limitations under the License.
               */
              pragma solidity 0.6.12;
              import { EIP712Domain } from "./EIP712Domain.sol"; // solhint-disable-line no-unused-import
              import { Blacklistable } from "../v1/Blacklistable.sol"; // solhint-disable-line no-unused-import
              import { FiatTokenV1 } from "../v1/FiatTokenV1.sol"; // solhint-disable-line no-unused-import
              import { FiatTokenV2 } from "./FiatTokenV2.sol"; // solhint-disable-line no-unused-import
              import { FiatTokenV2_1 } from "./FiatTokenV2_1.sol";
              import { EIP712 } from "../util/EIP712.sol";
              // solhint-disable func-name-mixedcase
              /**
               * @title FiatToken V2.2
               * @notice ERC20 Token backed by fiat reserves, version 2.2
               */
              contract FiatTokenV2_2 is FiatTokenV2_1 {
                  /**
                   * @notice Initialize v2.2
                   * @param accountsToBlacklist   A list of accounts to migrate from the old blacklist
                   * @param newSymbol             New token symbol
                   * data structure to the new blacklist data structure.
                   */
                  function initializeV2_2(
                      address[] calldata accountsToBlacklist,
                      string calldata newSymbol
                  ) external {
                      // solhint-disable-next-line reason-string
                      require(_initializedVersion == 2);
                      // Update fiat token symbol
                      symbol = newSymbol;
                      // Add previously blacklisted accounts to the new blacklist data structure
                      // and remove them from the old blacklist data structure.
                      for (uint256 i = 0; i < accountsToBlacklist.length; i++) {
                          require(
                              _deprecatedBlacklisted[accountsToBlacklist[i]],
                              "FiatTokenV2_2: Blacklisting previously unblacklisted account!"
                          );
                          _blacklist(accountsToBlacklist[i]);
                          delete _deprecatedBlacklisted[accountsToBlacklist[i]];
                      }
                      _blacklist(address(this));
                      delete _deprecatedBlacklisted[address(this)];
                      _initializedVersion = 3;
                  }
                  /**
                   * @dev Internal function to get the current chain id.
                   * @return The current chain id.
                   */
                  function _chainId() internal virtual view returns (uint256) {
                      uint256 chainId;
                      assembly {
                          chainId := chainid()
                      }
                      return chainId;
                  }
                  /**
                   * @inheritdoc EIP712Domain
                   */
                  function _domainSeparator() internal override view returns (bytes32) {
                      return EIP712.makeDomainSeparator(name, "2", _chainId());
                  }
                  /**
                   * @notice Update allowance with a signed permit
                   * @dev EOA wallet signatures should be packed in the order of r, s, v.
                   * @param owner       Token owner's address (Authorizer)
                   * @param spender     Spender's address
                   * @param value       Amount of allowance
                   * @param deadline    The time at which the signature expires (unix time), or max uint256 value to signal no expiration
                   * @param signature   Signature bytes signed by an EOA wallet or a contract wallet
                   */
                  function permit(
                      address owner,
                      address spender,
                      uint256 value,
                      uint256 deadline,
                      bytes memory signature
                  ) external whenNotPaused {
                      _permit(owner, spender, value, deadline, signature);
                  }
                  /**
                   * @notice Execute a transfer with a signed authorization
                   * @dev EOA wallet signatures should be packed in the order of r, s, v.
                   * @param from          Payer's address (Authorizer)
                   * @param to            Payee's address
                   * @param value         Amount to be transferred
                   * @param validAfter    The time after which this is valid (unix time)
                   * @param validBefore   The time before which this is valid (unix time)
                   * @param nonce         Unique nonce
                   * @param signature     Signature bytes signed by an EOA wallet or a contract wallet
                   */
                  function transferWithAuthorization(
                      address from,
                      address to,
                      uint256 value,
                      uint256 validAfter,
                      uint256 validBefore,
                      bytes32 nonce,
                      bytes memory signature
                  ) external whenNotPaused notBlacklisted(from) notBlacklisted(to) {
                      _transferWithAuthorization(
                          from,
                          to,
                          value,
                          validAfter,
                          validBefore,
                          nonce,
                          signature
                      );
                  }
                  /**
                   * @notice Receive a transfer with a signed authorization from the payer
                   * @dev This has an additional check to ensure that the payee's address
                   * matches the caller of this function to prevent front-running attacks.
                   * EOA wallet signatures should be packed in the order of r, s, v.
                   * @param from          Payer's address (Authorizer)
                   * @param to            Payee's address
                   * @param value         Amount to be transferred
                   * @param validAfter    The time after which this is valid (unix time)
                   * @param validBefore   The time before which this is valid (unix time)
                   * @param nonce         Unique nonce
                   * @param signature     Signature bytes signed by an EOA wallet or a contract wallet
                   */
                  function receiveWithAuthorization(
                      address from,
                      address to,
                      uint256 value,
                      uint256 validAfter,
                      uint256 validBefore,
                      bytes32 nonce,
                      bytes memory signature
                  ) external whenNotPaused notBlacklisted(from) notBlacklisted(to) {
                      _receiveWithAuthorization(
                          from,
                          to,
                          value,
                          validAfter,
                          validBefore,
                          nonce,
                          signature
                      );
                  }
                  /**
                   * @notice Attempt to cancel an authorization
                   * @dev Works only if the authorization is not yet used.
                   * EOA wallet signatures should be packed in the order of r, s, v.
                   * @param authorizer    Authorizer's address
                   * @param nonce         Nonce of the authorization
                   * @param signature     Signature bytes signed by an EOA wallet or a contract wallet
                   */
                  function cancelAuthorization(
                      address authorizer,
                      bytes32 nonce,
                      bytes memory signature
                  ) external whenNotPaused {
                      _cancelAuthorization(authorizer, nonce, signature);
                  }
                  /**
                   * @dev Helper method that sets the blacklist state of an account on balanceAndBlacklistStates.
                   * If _shouldBlacklist is true, we apply a (1 << 255) bitmask with an OR operation on the
                   * account's balanceAndBlacklistState. This flips the high bit for the account to 1,
                   * indicating that the account is blacklisted.
                   *
                   * If _shouldBlacklist if false, we reset the account's balanceAndBlacklistStates to their
                   * balances. This clears the high bit for the account, indicating that the account is unblacklisted.
                   * @param _account         The address of the account.
                   * @param _shouldBlacklist True if the account should be blacklisted, false if the account should be unblacklisted.
                   */
                  function _setBlacklistState(address _account, bool _shouldBlacklist)
                      internal
                      override
                  {
                      balanceAndBlacklistStates[_account] = _shouldBlacklist
                          ? balanceAndBlacklistStates[_account] | (1 << 255)
                          : _balanceOf(_account);
                  }
                  /**
                   * @dev Helper method that sets the balance of an account on balanceAndBlacklistStates.
                   * Since balances are stored in the last 255 bits of the balanceAndBlacklistStates value,
                   * we need to ensure that the updated balance does not exceed (2^255 - 1).
                   * Since blacklisted accounts' balances cannot be updated, the method will also
                   * revert if the account is blacklisted
                   * @param _account The address of the account.
                   * @param _balance The new fiat token balance of the account (max: (2^255 - 1)).
                   */
                  function _setBalance(address _account, uint256 _balance) internal override {
                      require(
                          _balance <= ((1 << 255) - 1),
                          "FiatTokenV2_2: Balance exceeds (2^255 - 1)"
                      );
                      require(
                          !_isBlacklisted(_account),
                          "FiatTokenV2_2: Account is blacklisted"
                      );
                      balanceAndBlacklistStates[_account] = _balance;
                  }
                  /**
                   * @inheritdoc Blacklistable
                   */
                  function _isBlacklisted(address _account)
                      internal
                      override
                      view
                      returns (bool)
                  {
                      return balanceAndBlacklistStates[_account] >> 255 == 1;
                  }
                  /**
                   * @dev Helper method to obtain the balance of an account. Since balances
                   * are stored in the last 255 bits of the balanceAndBlacklistStates value,
                   * we apply a ((1 << 255) - 1) bit bitmask with an AND operation on the
                   * balanceAndBlacklistState to obtain the balance.
                   * @param _account  The address of the account.
                   * @return          The fiat token balance of the account.
                   */
                  function _balanceOf(address _account)
                      internal
                      override
                      view
                      returns (uint256)
                  {
                      return balanceAndBlacklistStates[_account] & ((1 << 255) - 1);
                  }
                  /**
                   * @inheritdoc FiatTokenV1
                   */
                  function approve(address spender, uint256 value)
                      external
                      override
                      whenNotPaused
                      returns (bool)
                  {
                      _approve(msg.sender, spender, value);
                      return true;
                  }
                  /**
                   * @inheritdoc FiatTokenV2
                   */
                  function permit(
                      address owner,
                      address spender,
                      uint256 value,
                      uint256 deadline,
                      uint8 v,
                      bytes32 r,
                      bytes32 s
                  ) external override whenNotPaused {
                      _permit(owner, spender, value, deadline, v, r, s);
                  }
                  /**
                   * @inheritdoc FiatTokenV2
                   */
                  function increaseAllowance(address spender, uint256 increment)
                      external
                      override
                      whenNotPaused
                      returns (bool)
                  {
                      _increaseAllowance(msg.sender, spender, increment);
                      return true;
                  }
                  /**
                   * @inheritdoc FiatTokenV2
                   */
                  function decreaseAllowance(address spender, uint256 decrement)
                      external
                      override
                      whenNotPaused
                      returns (bool)
                  {
                      _decreaseAllowance(msg.sender, spender, decrement);
                      return true;
                  }
              }
              // SPDX-License-Identifier: MIT
              pragma solidity >=0.6.2 <0.8.0;
              /**
               * @dev Collection of functions related to the address type
               */
              library Address {
                  /**
                   * @dev Returns true if `account` is a contract.
                   *
                   * [IMPORTANT]
                   * ====
                   * It is unsafe to assume that an address for which this function returns
                   * false is an externally-owned account (EOA) and not a contract.
                   *
                   * Among others, `isContract` will return false for the following
                   * types of addresses:
                   *
                   *  - an externally-owned account
                   *  - a contract in construction
                   *  - an address where a contract will be created
                   *  - an address where a contract lived, but was destroyed
                   * ====
                   */
                  function isContract(address account) internal view returns (bool) {
                      // This method relies on extcodesize, which returns 0 for contracts in
                      // construction, since the code is only stored at the end of the
                      // constructor execution.
                      uint256 size;
                      // solhint-disable-next-line no-inline-assembly
                      assembly { size := extcodesize(account) }
                      return size > 0;
                  }
                  /**
                   * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
                   * `recipient`, forwarding all available gas and reverting on errors.
                   *
                   * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
                   * of certain opcodes, possibly making contracts go over the 2300 gas limit
                   * imposed by `transfer`, making them unable to receive funds via
                   * `transfer`. {sendValue} removes this limitation.
                   *
                   * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
                   *
                   * IMPORTANT: because control is transferred to `recipient`, care must be
                   * taken to not create reentrancy vulnerabilities. Consider using
                   * {ReentrancyGuard} or the
                   * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
                   */
                  function sendValue(address payable recipient, uint256 amount) internal {
                      require(address(this).balance >= amount, "Address: insufficient balance");
                      // solhint-disable-next-line avoid-low-level-calls, avoid-call-value
                      (bool success, ) = recipient.call{ value: amount }("");
                      require(success, "Address: unable to send value, recipient may have reverted");
                  }
                  /**
                   * @dev Performs a Solidity function call using a low level `call`. A
                   * plain`call` is an unsafe replacement for a function call: use this
                   * function instead.
                   *
                   * If `target` reverts with a revert reason, it is bubbled up by this
                   * function (like regular Solidity function calls).
                   *
                   * Returns the raw returned data. To convert to the expected return value,
                   * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
                   *
                   * Requirements:
                   *
                   * - `target` must be a contract.
                   * - calling `target` with `data` must not revert.
                   *
                   * _Available since v3.1._
                   */
                  function functionCall(address target, bytes memory data) internal returns (bytes memory) {
                    return functionCall(target, data, "Address: low-level call failed");
                  }
                  /**
                   * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
                   * `errorMessage` as a fallback revert reason when `target` reverts.
                   *
                   * _Available since v3.1._
                   */
                  function functionCall(address target, bytes memory data, string memory errorMessage) internal returns (bytes memory) {
                      return functionCallWithValue(target, data, 0, errorMessage);
                  }
                  /**
                   * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
                   * but also transferring `value` wei to `target`.
                   *
                   * Requirements:
                   *
                   * - the calling contract must have an ETH balance of at least `value`.
                   * - the called Solidity function must be `payable`.
                   *
                   * _Available since v3.1._
                   */
                  function functionCallWithValue(address target, bytes memory data, uint256 value) internal returns (bytes memory) {
                      return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
                  }
                  /**
                   * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
                   * with `errorMessage` as a fallback revert reason when `target` reverts.
                   *
                   * _Available since v3.1._
                   */
                  function functionCallWithValue(address target, bytes memory data, uint256 value, string memory errorMessage) internal returns (bytes memory) {
                      require(address(this).balance >= value, "Address: insufficient balance for call");
                      require(isContract(target), "Address: call to non-contract");
                      // solhint-disable-next-line avoid-low-level-calls
                      (bool success, bytes memory returndata) = target.call{ value: value }(data);
                      return _verifyCallResult(success, returndata, errorMessage);
                  }
                  /**
                   * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
                   * but performing a static call.
                   *
                   * _Available since v3.3._
                   */
                  function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
                      return functionStaticCall(target, data, "Address: low-level static call failed");
                  }
                  /**
                   * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
                   * but performing a static call.
                   *
                   * _Available since v3.3._
                   */
                  function functionStaticCall(address target, bytes memory data, string memory errorMessage) internal view returns (bytes memory) {
                      require(isContract(target), "Address: static call to non-contract");
                      // solhint-disable-next-line avoid-low-level-calls
                      (bool success, bytes memory returndata) = target.staticcall(data);
                      return _verifyCallResult(success, returndata, errorMessage);
                  }
                  /**
                   * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
                   * but performing a delegate call.
                   *
                   * _Available since v3.4._
                   */
                  function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {
                      return functionDelegateCall(target, data, "Address: low-level delegate call failed");
                  }
                  /**
                   * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
                   * but performing a delegate call.
                   *
                   * _Available since v3.4._
                   */
                  function functionDelegateCall(address target, bytes memory data, string memory errorMessage) internal returns (bytes memory) {
                      require(isContract(target), "Address: delegate call to non-contract");
                      // solhint-disable-next-line avoid-low-level-calls
                      (bool success, bytes memory returndata) = target.delegatecall(data);
                      return _verifyCallResult(success, returndata, errorMessage);
                  }
                  function _verifyCallResult(bool success, bytes memory returndata, string memory errorMessage) private pure returns(bytes memory) {
                      if (success) {
                          return returndata;
                      } else {
                          // Look for revert reason and bubble it up if present
                          if (returndata.length > 0) {
                              // The easiest way to bubble the revert reason is using memory via assembly
                              // solhint-disable-next-line no-inline-assembly
                              assembly {
                                  let returndata_size := mload(returndata)
                                  revert(add(32, returndata), returndata_size)
                              }
                          } else {
                              revert(errorMessage);
                          }
                      }
                  }
              }
              // SPDX-License-Identifier: MIT
              pragma solidity >=0.6.0 <0.8.0;
              import "./IERC20.sol";
              import "../../math/SafeMath.sol";
              import "../../utils/Address.sol";
              /**
               * @title SafeERC20
               * @dev Wrappers around ERC20 operations that throw on failure (when the token
               * contract returns false). Tokens that return no value (and instead revert or
               * throw on failure) are also supported, non-reverting calls are assumed to be
               * successful.
               * To use this library you can add a `using SafeERC20 for IERC20;` statement to your contract,
               * which allows you to call the safe operations as `token.safeTransfer(...)`, etc.
               */
              library SafeERC20 {
                  using SafeMath for uint256;
                  using Address for address;
                  function safeTransfer(IERC20 token, address to, uint256 value) internal {
                      _callOptionalReturn(token, abi.encodeWithSelector(token.transfer.selector, to, value));
                  }
                  function safeTransferFrom(IERC20 token, address from, address to, uint256 value) internal {
                      _callOptionalReturn(token, abi.encodeWithSelector(token.transferFrom.selector, from, to, value));
                  }
                  /**
                   * @dev Deprecated. This function has issues similar to the ones found in
                   * {IERC20-approve}, and its usage is discouraged.
                   *
                   * Whenever possible, use {safeIncreaseAllowance} and
                   * {safeDecreaseAllowance} instead.
                   */
                  function safeApprove(IERC20 token, address spender, uint256 value) internal {
                      // safeApprove should only be called when setting an initial allowance,
                      // or when resetting it to zero. To increase and decrease it, use
                      // 'safeIncreaseAllowance' and 'safeDecreaseAllowance'
                      // solhint-disable-next-line max-line-length
                      require((value == 0) || (token.allowance(address(this), spender) == 0),
                          "SafeERC20: approve from non-zero to non-zero allowance"
                      );
                      _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, value));
                  }
                  function safeIncreaseAllowance(IERC20 token, address spender, uint256 value) internal {
                      uint256 newAllowance = token.allowance(address(this), spender).add(value);
                      _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
                  }
                  function safeDecreaseAllowance(IERC20 token, address spender, uint256 value) internal {
                      uint256 newAllowance = token.allowance(address(this), spender).sub(value, "SafeERC20: decreased allowance below zero");
                      _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
                  }
                  /**
                   * @dev Imitates a Solidity high-level call (i.e. a regular function call to a contract), relaxing the requirement
                   * on the return value: the return value is optional (but if data is returned, it must not be false).
                   * @param token The token targeted by the call.
                   * @param data The call data (encoded using abi.encode or one of its variants).
                   */
                  function _callOptionalReturn(IERC20 token, bytes memory data) private {
                      // We need to perform a low level call here, to bypass Solidity's return data size checking mechanism, since
                      // we're implementing it ourselves. We use {Address.functionCall} to perform this call, which verifies that
                      // the target address contains contract code and also asserts for success in the low-level call.
                      bytes memory returndata = address(token).functionCall(data, "SafeERC20: low-level call failed");
                      if (returndata.length > 0) { // Return data is optional
                          // solhint-disable-next-line max-line-length
                          require(abi.decode(returndata, (bool)), "SafeERC20: ERC20 operation did not succeed");
                      }
                  }
              }
              // SPDX-License-Identifier: MIT
              pragma solidity >=0.6.0 <0.8.0;
              /**
               * @dev Interface of the ERC20 standard as defined in the EIP.
               */
              interface IERC20 {
                  /**
                   * @dev Returns the amount of tokens in existence.
                   */
                  function totalSupply() external view returns (uint256);
                  /**
                   * @dev Returns the amount of tokens owned by `account`.
                   */
                  function balanceOf(address account) external view returns (uint256);
                  /**
                   * @dev Moves `amount` tokens from the caller's account to `recipient`.
                   *
                   * Returns a boolean value indicating whether the operation succeeded.
                   *
                   * Emits a {Transfer} event.
                   */
                  function transfer(address recipient, uint256 amount) external returns (bool);
                  /**
                   * @dev Returns the remaining number of tokens that `spender` will be
                   * allowed to spend on behalf of `owner` through {transferFrom}. This is
                   * zero by default.
                   *
                   * This value changes when {approve} or {transferFrom} are called.
                   */
                  function allowance(address owner, address spender) external view returns (uint256);
                  /**
                   * @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
                   *
                   * Returns a boolean value indicating whether the operation succeeded.
                   *
                   * IMPORTANT: Beware that changing an allowance with this method brings the risk
                   * that someone may use both the old and the new allowance by unfortunate
                   * transaction ordering. One possible solution to mitigate this race
                   * condition is to first reduce the spender's allowance to 0 and set the
                   * desired value afterwards:
                   * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
                   *
                   * Emits an {Approval} event.
                   */
                  function approve(address spender, uint256 amount) external returns (bool);
                  /**
                   * @dev Moves `amount` tokens from `sender` to `recipient` using the
                   * allowance mechanism. `amount` is then deducted from the caller's
                   * allowance.
                   *
                   * Returns a boolean value indicating whether the operation succeeded.
                   *
                   * Emits a {Transfer} event.
                   */
                  function transferFrom(address sender, address recipient, uint256 amount) external returns (bool);
                  /**
                   * @dev Emitted when `value` tokens are moved from one account (`from`) to
                   * another (`to`).
                   *
                   * Note that `value` may be zero.
                   */
                  event Transfer(address indexed from, address indexed to, uint256 value);
                  /**
                   * @dev Emitted when the allowance of a `spender` for an `owner` is set by
                   * a call to {approve}. `value` is the new allowance.
                   */
                  event Approval(address indexed owner, address indexed spender, uint256 value);
              }
              // SPDX-License-Identifier: MIT
              pragma solidity >=0.6.0 <0.8.0;
              /**
               * @dev Wrappers over Solidity's arithmetic operations with added overflow
               * checks.
               *
               * Arithmetic operations in Solidity wrap on overflow. This can easily result
               * in bugs, because programmers usually assume that an overflow raises an
               * error, which is the standard behavior in high level programming languages.
               * `SafeMath` restores this intuition by reverting the transaction when an
               * operation overflows.
               *
               * Using this library instead of the unchecked operations eliminates an entire
               * class of bugs, so it's recommended to use it always.
               */
              library SafeMath {
                  /**
                   * @dev Returns the addition of two unsigned integers, with an overflow flag.
                   *
                   * _Available since v3.4._
                   */
                  function tryAdd(uint256 a, uint256 b) internal pure returns (bool, uint256) {
                      uint256 c = a + b;
                      if (c < a) return (false, 0);
                      return (true, c);
                  }
                  /**
                   * @dev Returns the substraction of two unsigned integers, with an overflow flag.
                   *
                   * _Available since v3.4._
                   */
                  function trySub(uint256 a, uint256 b) internal pure returns (bool, uint256) {
                      if (b > a) return (false, 0);
                      return (true, a - b);
                  }
                  /**
                   * @dev Returns the multiplication of two unsigned integers, with an overflow flag.
                   *
                   * _Available since v3.4._
                   */
                  function tryMul(uint256 a, uint256 b) internal pure returns (bool, uint256) {
                      // Gas optimization: this is cheaper than requiring 'a' not being zero, but the
                      // benefit is lost if 'b' is also tested.
                      // See: https://github.com/OpenZeppelin/openzeppelin-contracts/pull/522
                      if (a == 0) return (true, 0);
                      uint256 c = a * b;
                      if (c / a != b) return (false, 0);
                      return (true, c);
                  }
                  /**
                   * @dev Returns the division of two unsigned integers, with a division by zero flag.
                   *
                   * _Available since v3.4._
                   */
                  function tryDiv(uint256 a, uint256 b) internal pure returns (bool, uint256) {
                      if (b == 0) return (false, 0);
                      return (true, a / b);
                  }
                  /**
                   * @dev Returns the remainder of dividing two unsigned integers, with a division by zero flag.
                   *
                   * _Available since v3.4._
                   */
                  function tryMod(uint256 a, uint256 b) internal pure returns (bool, uint256) {
                      if (b == 0) return (false, 0);
                      return (true, a % b);
                  }
                  /**
                   * @dev Returns the addition of two unsigned integers, reverting on
                   * overflow.
                   *
                   * Counterpart to Solidity's `+` operator.
                   *
                   * Requirements:
                   *
                   * - Addition cannot overflow.
                   */
                  function add(uint256 a, uint256 b) internal pure returns (uint256) {
                      uint256 c = a + b;
                      require(c >= a, "SafeMath: addition overflow");
                      return c;
                  }
                  /**
                   * @dev Returns the subtraction of two unsigned integers, reverting on
                   * overflow (when the result is negative).
                   *
                   * Counterpart to Solidity's `-` operator.
                   *
                   * Requirements:
                   *
                   * - Subtraction cannot overflow.
                   */
                  function sub(uint256 a, uint256 b) internal pure returns (uint256) {
                      require(b <= a, "SafeMath: subtraction overflow");
                      return a - b;
                  }
                  /**
                   * @dev Returns the multiplication of two unsigned integers, reverting on
                   * overflow.
                   *
                   * Counterpart to Solidity's `*` operator.
                   *
                   * Requirements:
                   *
                   * - Multiplication cannot overflow.
                   */
                  function mul(uint256 a, uint256 b) internal pure returns (uint256) {
                      if (a == 0) return 0;
                      uint256 c = a * b;
                      require(c / a == b, "SafeMath: multiplication overflow");
                      return c;
                  }
                  /**
                   * @dev Returns the integer division of two unsigned integers, reverting on
                   * division by zero. The result is rounded towards zero.
                   *
                   * Counterpart to Solidity's `/` operator. Note: this function uses a
                   * `revert` opcode (which leaves remaining gas untouched) while Solidity
                   * uses an invalid opcode to revert (consuming all remaining gas).
                   *
                   * Requirements:
                   *
                   * - The divisor cannot be zero.
                   */
                  function div(uint256 a, uint256 b) internal pure returns (uint256) {
                      require(b > 0, "SafeMath: division by zero");
                      return a / b;
                  }
                  /**
                   * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
                   * reverting when dividing by zero.
                   *
                   * Counterpart to Solidity's `%` operator. This function uses a `revert`
                   * opcode (which leaves remaining gas untouched) while Solidity uses an
                   * invalid opcode to revert (consuming all remaining gas).
                   *
                   * Requirements:
                   *
                   * - The divisor cannot be zero.
                   */
                  function mod(uint256 a, uint256 b) internal pure returns (uint256) {
                      require(b > 0, "SafeMath: modulo by zero");
                      return a % b;
                  }
                  /**
                   * @dev Returns the subtraction of two unsigned integers, reverting with custom message on
                   * overflow (when the result is negative).
                   *
                   * CAUTION: This function is deprecated because it requires allocating memory for the error
                   * message unnecessarily. For custom revert reasons use {trySub}.
                   *
                   * Counterpart to Solidity's `-` operator.
                   *
                   * Requirements:
                   *
                   * - Subtraction cannot overflow.
                   */
                  function sub(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
                      require(b <= a, errorMessage);
                      return a - b;
                  }
                  /**
                   * @dev Returns the integer division of two unsigned integers, reverting with custom message on
                   * division by zero. The result is rounded towards zero.
                   *
                   * CAUTION: This function is deprecated because it requires allocating memory for the error
                   * message unnecessarily. For custom revert reasons use {tryDiv}.
                   *
                   * Counterpart to Solidity's `/` operator. Note: this function uses a
                   * `revert` opcode (which leaves remaining gas untouched) while Solidity
                   * uses an invalid opcode to revert (consuming all remaining gas).
                   *
                   * Requirements:
                   *
                   * - The divisor cannot be zero.
                   */
                  function div(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
                      require(b > 0, errorMessage);
                      return a / b;
                  }
                  /**
                   * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
                   * reverting with custom message when dividing by zero.
                   *
                   * CAUTION: This function is deprecated because it requires allocating memory for the error
                   * message unnecessarily. For custom revert reasons use {tryMod}.
                   *
                   * Counterpart to Solidity's `%` operator. This function uses a `revert`
                   * opcode (which leaves remaining gas untouched) while Solidity uses an
                   * invalid opcode to revert (consuming all remaining gas).
                   *
                   * Requirements:
                   *
                   * - The divisor cannot be zero.
                   */
                  function mod(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
                      require(b > 0, errorMessage);
                      return a % b;
                  }
              }
              /**
               * SPDX-License-Identifier: Apache-2.0
               *
               * Copyright (c) 2023, Circle Internet Financial, LLC.
               *
               * Licensed under the Apache License, Version 2.0 (the "License");
               * you may not use this file except in compliance with the License.
               * You may obtain a copy of the License at
               *
               * http://www.apache.org/licenses/LICENSE-2.0
               *
               * Unless required by applicable law or agreed to in writing, software
               * distributed under the License is distributed on an "AS IS" BASIS,
               * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
               * See the License for the specific language governing permissions and
               * limitations under the License.
               */
              pragma solidity 0.6.12;
              import { FiatTokenV2 } from "./FiatTokenV2.sol";
              // solhint-disable func-name-mixedcase
              /**
               * @title FiatToken V2.1
               * @notice ERC20 Token backed by fiat reserves, version 2.1
               */
              contract FiatTokenV2_1 is FiatTokenV2 {
                  /**
                   * @notice Initialize v2.1
                   * @param lostAndFound  The address to which the locked funds are sent
                   */
                  function initializeV2_1(address lostAndFound) external {
                      // solhint-disable-next-line reason-string
                      require(_initializedVersion == 1);
                      uint256 lockedAmount = _balanceOf(address(this));
                      if (lockedAmount > 0) {
                          _transfer(address(this), lostAndFound, lockedAmount);
                      }
                      _blacklist(address(this));
                      _initializedVersion = 2;
                  }
                  /**
                   * @notice Version string for the EIP712 domain separator
                   * @return Version string
                   */
                  function version() external pure returns (string memory) {
                      return "2";
                  }
              }
              /**
               * SPDX-License-Identifier: Apache-2.0
               *
               * Copyright (c) 2023, Circle Internet Financial, LLC.
               *
               * Licensed under the Apache License, Version 2.0 (the "License");
               * you may not use this file except in compliance with the License.
               * You may obtain a copy of the License at
               *
               * http://www.apache.org/licenses/LICENSE-2.0
               *
               * Unless required by applicable law or agreed to in writing, software
               * distributed under the License is distributed on an "AS IS" BASIS,
               * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
               * See the License for the specific language governing permissions and
               * limitations under the License.
               */
              pragma solidity 0.6.12;
              import { FiatTokenV1_1 } from "../v1.1/FiatTokenV1_1.sol";
              import { EIP712 } from "../util/EIP712.sol";
              import { EIP3009 } from "./EIP3009.sol";
              import { EIP2612 } from "./EIP2612.sol";
              /**
               * @title FiatToken V2
               * @notice ERC20 Token backed by fiat reserves, version 2
               */
              contract FiatTokenV2 is FiatTokenV1_1, EIP3009, EIP2612 {
                  uint8 internal _initializedVersion;
                  /**
                   * @notice Initialize v2
                   * @param newName   New token name
                   */
                  function initializeV2(string calldata newName) external {
                      // solhint-disable-next-line reason-string
                      require(initialized && _initializedVersion == 0);
                      name = newName;
                      _DEPRECATED_CACHED_DOMAIN_SEPARATOR = EIP712.makeDomainSeparator(
                          newName,
                          "2"
                      );
                      _initializedVersion = 1;
                  }
                  /**
                   * @notice Increase the allowance by a given increment
                   * @param spender   Spender's address
                   * @param increment Amount of increase in allowance
                   * @return True if successful
                   */
                  function increaseAllowance(address spender, uint256 increment)
                      external
                      virtual
                      whenNotPaused
                      notBlacklisted(msg.sender)
                      notBlacklisted(spender)
                      returns (bool)
                  {
                      _increaseAllowance(msg.sender, spender, increment);
                      return true;
                  }
                  /**
                   * @notice Decrease the allowance by a given decrement
                   * @param spender   Spender's address
                   * @param decrement Amount of decrease in allowance
                   * @return True if successful
                   */
                  function decreaseAllowance(address spender, uint256 decrement)
                      external
                      virtual
                      whenNotPaused
                      notBlacklisted(msg.sender)
                      notBlacklisted(spender)
                      returns (bool)
                  {
                      _decreaseAllowance(msg.sender, spender, decrement);
                      return true;
                  }
                  /**
                   * @notice Execute a transfer with a signed authorization
                   * @param from          Payer's address (Authorizer)
                   * @param to            Payee's address
                   * @param value         Amount to be transferred
                   * @param validAfter    The time after which this is valid (unix time)
                   * @param validBefore   The time before which this is valid (unix time)
                   * @param nonce         Unique nonce
                   * @param v             v of the signature
                   * @param r             r of the signature
                   * @param s             s of the signature
                   */
                  function transferWithAuthorization(
                      address from,
                      address to,
                      uint256 value,
                      uint256 validAfter,
                      uint256 validBefore,
                      bytes32 nonce,
                      uint8 v,
                      bytes32 r,
                      bytes32 s
                  ) external whenNotPaused notBlacklisted(from) notBlacklisted(to) {
                      _transferWithAuthorization(
                          from,
                          to,
                          value,
                          validAfter,
                          validBefore,
                          nonce,
                          v,
                          r,
                          s
                      );
                  }
                  /**
                   * @notice Receive a transfer with a signed authorization from the payer
                   * @dev This has an additional check to ensure that the payee's address
                   * matches the caller of this function to prevent front-running attacks.
                   * @param from          Payer's address (Authorizer)
                   * @param to            Payee's address
                   * @param value         Amount to be transferred
                   * @param validAfter    The time after which this is valid (unix time)
                   * @param validBefore   The time before which this is valid (unix time)
                   * @param nonce         Unique nonce
                   * @param v             v of the signature
                   * @param r             r of the signature
                   * @param s             s of the signature
                   */
                  function receiveWithAuthorization(
                      address from,
                      address to,
                      uint256 value,
                      uint256 validAfter,
                      uint256 validBefore,
                      bytes32 nonce,
                      uint8 v,
                      bytes32 r,
                      bytes32 s
                  ) external whenNotPaused notBlacklisted(from) notBlacklisted(to) {
                      _receiveWithAuthorization(
                          from,
                          to,
                          value,
                          validAfter,
                          validBefore,
                          nonce,
                          v,
                          r,
                          s
                      );
                  }
                  /**
                   * @notice Attempt to cancel an authorization
                   * @dev Works only if the authorization is not yet used.
                   * @param authorizer    Authorizer's address
                   * @param nonce         Nonce of the authorization
                   * @param v             v of the signature
                   * @param r             r of the signature
                   * @param s             s of the signature
                   */
                  function cancelAuthorization(
                      address authorizer,
                      bytes32 nonce,
                      uint8 v,
                      bytes32 r,
                      bytes32 s
                  ) external whenNotPaused {
                      _cancelAuthorization(authorizer, nonce, v, r, s);
                  }
                  /**
                   * @notice Update allowance with a signed permit
                   * @param owner       Token owner's address (Authorizer)
                   * @param spender     Spender's address
                   * @param value       Amount of allowance
                   * @param deadline    The time at which the signature expires (unix time), or max uint256 value to signal no expiration
                   * @param v           v of the signature
                   * @param r           r of the signature
                   * @param s           s of the signature
                   */
                  function permit(
                      address owner,
                      address spender,
                      uint256 value,
                      uint256 deadline,
                      uint8 v,
                      bytes32 r,
                      bytes32 s
                  )
                      external
                      virtual
                      whenNotPaused
                      notBlacklisted(owner)
                      notBlacklisted(spender)
                  {
                      _permit(owner, spender, value, deadline, v, r, s);
                  }
                  /**
                   * @dev Internal function to increase the allowance by a given increment
                   * @param owner     Token owner's address
                   * @param spender   Spender's address
                   * @param increment Amount of increase
                   */
                  function _increaseAllowance(
                      address owner,
                      address spender,
                      uint256 increment
                  ) internal override {
                      _approve(owner, spender, allowed[owner][spender].add(increment));
                  }
                  /**
                   * @dev Internal function to decrease the allowance by a given decrement
                   * @param owner     Token owner's address
                   * @param spender   Spender's address
                   * @param decrement Amount of decrease
                   */
                  function _decreaseAllowance(
                      address owner,
                      address spender,
                      uint256 decrement
                  ) internal override {
                      _approve(
                          owner,
                          spender,
                          allowed[owner][spender].sub(
                              decrement,
                              "ERC20: decreased allowance below zero"
                          )
                      );
                  }
              }
              /**
               * SPDX-License-Identifier: Apache-2.0
               *
               * Copyright (c) 2023, Circle Internet Financial, LLC.
               *
               * Licensed under the Apache License, Version 2.0 (the "License");
               * you may not use this file except in compliance with the License.
               * You may obtain a copy of the License at
               *
               * http://www.apache.org/licenses/LICENSE-2.0
               *
               * Unless required by applicable law or agreed to in writing, software
               * distributed under the License is distributed on an "AS IS" BASIS,
               * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
               * See the License for the specific language governing permissions and
               * limitations under the License.
               */
              pragma solidity 0.6.12;
              // solhint-disable func-name-mixedcase
              /**
               * @title EIP712 Domain
               */
              contract EIP712Domain {
                  // was originally DOMAIN_SEPARATOR
                  // but that has been moved to a method so we can override it in V2_2+
                  bytes32 internal _DEPRECATED_CACHED_DOMAIN_SEPARATOR;
                  /**
                   * @notice Get the EIP712 Domain Separator.
                   * @return The bytes32 EIP712 domain separator.
                   */
                  function DOMAIN_SEPARATOR() external view returns (bytes32) {
                      return _domainSeparator();
                  }
                  /**
                   * @dev Internal method to get the EIP712 Domain Separator.
                   * @return The bytes32 EIP712 domain separator.
                   */
                  function _domainSeparator() internal virtual view returns (bytes32) {
                      return _DEPRECATED_CACHED_DOMAIN_SEPARATOR;
                  }
              }
              /**
               * SPDX-License-Identifier: Apache-2.0
               *
               * Copyright (c) 2023, Circle Internet Financial, LLC.
               *
               * Licensed under the Apache License, Version 2.0 (the "License");
               * you may not use this file except in compliance with the License.
               * You may obtain a copy of the License at
               *
               * http://www.apache.org/licenses/LICENSE-2.0
               *
               * Unless required by applicable law or agreed to in writing, software
               * distributed under the License is distributed on an "AS IS" BASIS,
               * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
               * See the License for the specific language governing permissions and
               * limitations under the License.
               */
              pragma solidity 0.6.12;
              import { AbstractFiatTokenV2 } from "./AbstractFiatTokenV2.sol";
              import { EIP712Domain } from "./EIP712Domain.sol";
              import { SignatureChecker } from "../util/SignatureChecker.sol";
              import { MessageHashUtils } from "../util/MessageHashUtils.sol";
              /**
               * @title EIP-3009
               * @notice Provide internal implementation for gas-abstracted transfers
               * @dev Contracts that inherit from this must wrap these with publicly
               * accessible functions, optionally adding modifiers where necessary
               */
              abstract contract EIP3009 is AbstractFiatTokenV2, EIP712Domain {
                  // keccak256("TransferWithAuthorization(address from,address to,uint256 value,uint256 validAfter,uint256 validBefore,bytes32 nonce)")
                  bytes32
                      public constant TRANSFER_WITH_AUTHORIZATION_TYPEHASH = 0x7c7c6cdb67a18743f49ec6fa9b35f50d52ed05cbed4cc592e13b44501c1a2267;
                  // keccak256("ReceiveWithAuthorization(address from,address to,uint256 value,uint256 validAfter,uint256 validBefore,bytes32 nonce)")
                  bytes32
                      public constant RECEIVE_WITH_AUTHORIZATION_TYPEHASH = 0xd099cc98ef71107a616c4f0f941f04c322d8e254fe26b3c6668db87aae413de8;
                  // keccak256("CancelAuthorization(address authorizer,bytes32 nonce)")
                  bytes32
                      public constant CANCEL_AUTHORIZATION_TYPEHASH = 0x158b0a9edf7a828aad02f63cd515c68ef2f50ba807396f6d12842833a1597429;
                  /**
                   * @dev authorizer address => nonce => bool (true if nonce is used)
                   */
                  mapping(address => mapping(bytes32 => bool)) private _authorizationStates;
                  event AuthorizationUsed(address indexed authorizer, bytes32 indexed nonce);
                  event AuthorizationCanceled(
                      address indexed authorizer,
                      bytes32 indexed nonce
                  );
                  /**
                   * @notice Returns the state of an authorization
                   * @dev Nonces are randomly generated 32-byte data unique to the
                   * authorizer's address
                   * @param authorizer    Authorizer's address
                   * @param nonce         Nonce of the authorization
                   * @return True if the nonce is used
                   */
                  function authorizationState(address authorizer, bytes32 nonce)
                      external
                      view
                      returns (bool)
                  {
                      return _authorizationStates[authorizer][nonce];
                  }
                  /**
                   * @notice Execute a transfer with a signed authorization
                   * @param from          Payer's address (Authorizer)
                   * @param to            Payee's address
                   * @param value         Amount to be transferred
                   * @param validAfter    The time after which this is valid (unix time)
                   * @param validBefore   The time before which this is valid (unix time)
                   * @param nonce         Unique nonce
                   * @param v             v of the signature
                   * @param r             r of the signature
                   * @param s             s of the signature
                   */
                  function _transferWithAuthorization(
                      address from,
                      address to,
                      uint256 value,
                      uint256 validAfter,
                      uint256 validBefore,
                      bytes32 nonce,
                      uint8 v,
                      bytes32 r,
                      bytes32 s
                  ) internal {
                      _transferWithAuthorization(
                          from,
                          to,
                          value,
                          validAfter,
                          validBefore,
                          nonce,
                          abi.encodePacked(r, s, v)
                      );
                  }
                  /**
                   * @notice Execute a transfer with a signed authorization
                   * @dev EOA wallet signatures should be packed in the order of r, s, v.
                   * @param from          Payer's address (Authorizer)
                   * @param to            Payee's address
                   * @param value         Amount to be transferred
                   * @param validAfter    The time after which this is valid (unix time)
                   * @param validBefore   The time before which this is valid (unix time)
                   * @param nonce         Unique nonce
                   * @param signature     Signature byte array produced by an EOA wallet or a contract wallet
                   */
                  function _transferWithAuthorization(
                      address from,
                      address to,
                      uint256 value,
                      uint256 validAfter,
                      uint256 validBefore,
                      bytes32 nonce,
                      bytes memory signature
                  ) internal {
                      _requireValidAuthorization(from, nonce, validAfter, validBefore);
                      _requireValidSignature(
                          from,
                          keccak256(
                              abi.encode(
                                  TRANSFER_WITH_AUTHORIZATION_TYPEHASH,
                                  from,
                                  to,
                                  value,
                                  validAfter,
                                  validBefore,
                                  nonce
                              )
                          ),
                          signature
                      );
                      _markAuthorizationAsUsed(from, nonce);
                      _transfer(from, to, value);
                  }
                  /**
                   * @notice Receive a transfer with a signed authorization from the payer
                   * @dev This has an additional check to ensure that the payee's address
                   * matches the caller of this function to prevent front-running attacks.
                   * @param from          Payer's address (Authorizer)
                   * @param to            Payee's address
                   * @param value         Amount to be transferred
                   * @param validAfter    The time after which this is valid (unix time)
                   * @param validBefore   The time before which this is valid (unix time)
                   * @param nonce         Unique nonce
                   * @param v             v of the signature
                   * @param r             r of the signature
                   * @param s             s of the signature
                   */
                  function _receiveWithAuthorization(
                      address from,
                      address to,
                      uint256 value,
                      uint256 validAfter,
                      uint256 validBefore,
                      bytes32 nonce,
                      uint8 v,
                      bytes32 r,
                      bytes32 s
                  ) internal {
                      _receiveWithAuthorization(
                          from,
                          to,
                          value,
                          validAfter,
                          validBefore,
                          nonce,
                          abi.encodePacked(r, s, v)
                      );
                  }
                  /**
                   * @notice Receive a transfer with a signed authorization from the payer
                   * @dev This has an additional check to ensure that the payee's address
                   * matches the caller of this function to prevent front-running attacks.
                   * EOA wallet signatures should be packed in the order of r, s, v.
                   * @param from          Payer's address (Authorizer)
                   * @param to            Payee's address
                   * @param value         Amount to be transferred
                   * @param validAfter    The time after which this is valid (unix time)
                   * @param validBefore   The time before which this is valid (unix time)
                   * @param nonce         Unique nonce
                   * @param signature     Signature byte array produced by an EOA wallet or a contract wallet
                   */
                  function _receiveWithAuthorization(
                      address from,
                      address to,
                      uint256 value,
                      uint256 validAfter,
                      uint256 validBefore,
                      bytes32 nonce,
                      bytes memory signature
                  ) internal {
                      require(to == msg.sender, "FiatTokenV2: caller must be the payee");
                      _requireValidAuthorization(from, nonce, validAfter, validBefore);
                      _requireValidSignature(
                          from,
                          keccak256(
                              abi.encode(
                                  RECEIVE_WITH_AUTHORIZATION_TYPEHASH,
                                  from,
                                  to,
                                  value,
                                  validAfter,
                                  validBefore,
                                  nonce
                              )
                          ),
                          signature
                      );
                      _markAuthorizationAsUsed(from, nonce);
                      _transfer(from, to, value);
                  }
                  /**
                   * @notice Attempt to cancel an authorization
                   * @param authorizer    Authorizer's address
                   * @param nonce         Nonce of the authorization
                   * @param v             v of the signature
                   * @param r             r of the signature
                   * @param s             s of the signature
                   */
                  function _cancelAuthorization(
                      address authorizer,
                      bytes32 nonce,
                      uint8 v,
                      bytes32 r,
                      bytes32 s
                  ) internal {
                      _cancelAuthorization(authorizer, nonce, abi.encodePacked(r, s, v));
                  }
                  /**
                   * @notice Attempt to cancel an authorization
                   * @dev EOA wallet signatures should be packed in the order of r, s, v.
                   * @param authorizer    Authorizer's address
                   * @param nonce         Nonce of the authorization
                   * @param signature     Signature byte array produced by an EOA wallet or a contract wallet
                   */
                  function _cancelAuthorization(
                      address authorizer,
                      bytes32 nonce,
                      bytes memory signature
                  ) internal {
                      _requireUnusedAuthorization(authorizer, nonce);
                      _requireValidSignature(
                          authorizer,
                          keccak256(
                              abi.encode(CANCEL_AUTHORIZATION_TYPEHASH, authorizer, nonce)
                          ),
                          signature
                      );
                      _authorizationStates[authorizer][nonce] = true;
                      emit AuthorizationCanceled(authorizer, nonce);
                  }
                  /**
                   * @notice Validates that signature against input data struct
                   * @param signer        Signer's address
                   * @param dataHash      Hash of encoded data struct
                   * @param signature     Signature byte array produced by an EOA wallet or a contract wallet
                   */
                  function _requireValidSignature(
                      address signer,
                      bytes32 dataHash,
                      bytes memory signature
                  ) private view {
                      require(
                          SignatureChecker.isValidSignatureNow(
                              signer,
                              MessageHashUtils.toTypedDataHash(_domainSeparator(), dataHash),
                              signature
                          ),
                          "FiatTokenV2: invalid signature"
                      );
                  }
                  /**
                   * @notice Check that an authorization is unused
                   * @param authorizer    Authorizer's address
                   * @param nonce         Nonce of the authorization
                   */
                  function _requireUnusedAuthorization(address authorizer, bytes32 nonce)
                      private
                      view
                  {
                      require(
                          !_authorizationStates[authorizer][nonce],
                          "FiatTokenV2: authorization is used or canceled"
                      );
                  }
                  /**
                   * @notice Check that authorization is valid
                   * @param authorizer    Authorizer's address
                   * @param nonce         Nonce of the authorization
                   * @param validAfter    The time after which this is valid (unix time)
                   * @param validBefore   The time before which this is valid (unix time)
                   */
                  function _requireValidAuthorization(
                      address authorizer,
                      bytes32 nonce,
                      uint256 validAfter,
                      uint256 validBefore
                  ) private view {
                      require(
                          now > validAfter,
                          "FiatTokenV2: authorization is not yet valid"
                      );
                      require(now < validBefore, "FiatTokenV2: authorization is expired");
                      _requireUnusedAuthorization(authorizer, nonce);
                  }
                  /**
                   * @notice Mark an authorization as used
                   * @param authorizer    Authorizer's address
                   * @param nonce         Nonce of the authorization
                   */
                  function _markAuthorizationAsUsed(address authorizer, bytes32 nonce)
                      private
                  {
                      _authorizationStates[authorizer][nonce] = true;
                      emit AuthorizationUsed(authorizer, nonce);
                  }
              }
              /**
               * SPDX-License-Identifier: Apache-2.0
               *
               * Copyright (c) 2023, Circle Internet Financial, LLC.
               *
               * Licensed under the Apache License, Version 2.0 (the "License");
               * you may not use this file except in compliance with the License.
               * You may obtain a copy of the License at
               *
               * http://www.apache.org/licenses/LICENSE-2.0
               *
               * Unless required by applicable law or agreed to in writing, software
               * distributed under the License is distributed on an "AS IS" BASIS,
               * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
               * See the License for the specific language governing permissions and
               * limitations under the License.
               */
              pragma solidity 0.6.12;
              import { AbstractFiatTokenV2 } from "./AbstractFiatTokenV2.sol";
              import { EIP712Domain } from "./EIP712Domain.sol";
              import { MessageHashUtils } from "../util/MessageHashUtils.sol";
              import { SignatureChecker } from "../util/SignatureChecker.sol";
              /**
               * @title EIP-2612
               * @notice Provide internal implementation for gas-abstracted approvals
               */
              abstract contract EIP2612 is AbstractFiatTokenV2, EIP712Domain {
                  // keccak256("Permit(address owner,address spender,uint256 value,uint256 nonce,uint256 deadline)")
                  bytes32
                      public constant PERMIT_TYPEHASH = 0x6e71edae12b1b97f4d1f60370fef10105fa2faae0126114a169c64845d6126c9;
                  mapping(address => uint256) private _permitNonces;
                  /**
                   * @notice Nonces for permit
                   * @param owner Token owner's address (Authorizer)
                   * @return Next nonce
                   */
                  function nonces(address owner) external view returns (uint256) {
                      return _permitNonces[owner];
                  }
                  /**
                   * @notice Verify a signed approval permit and execute if valid
                   * @param owner     Token owner's address (Authorizer)
                   * @param spender   Spender's address
                   * @param value     Amount of allowance
                   * @param deadline  The time at which the signature expires (unix time), or max uint256 value to signal no expiration
                   * @param v         v of the signature
                   * @param r         r of the signature
                   * @param s         s of the signature
                   */
                  function _permit(
                      address owner,
                      address spender,
                      uint256 value,
                      uint256 deadline,
                      uint8 v,
                      bytes32 r,
                      bytes32 s
                  ) internal {
                      _permit(owner, spender, value, deadline, abi.encodePacked(r, s, v));
                  }
                  /**
                   * @notice Verify a signed approval permit and execute if valid
                   * @dev EOA wallet signatures should be packed in the order of r, s, v.
                   * @param owner      Token owner's address (Authorizer)
                   * @param spender    Spender's address
                   * @param value      Amount of allowance
                   * @param deadline   The time at which the signature expires (unix time), or max uint256 value to signal no expiration
                   * @param signature  Signature byte array signed by an EOA wallet or a contract wallet
                   */
                  function _permit(
                      address owner,
                      address spender,
                      uint256 value,
                      uint256 deadline,
                      bytes memory signature
                  ) internal {
                      require(
                          deadline == type(uint256).max || deadline >= now,
                          "FiatTokenV2: permit is expired"
                      );
                      bytes32 typedDataHash = MessageHashUtils.toTypedDataHash(
                          _domainSeparator(),
                          keccak256(
                              abi.encode(
                                  PERMIT_TYPEHASH,
                                  owner,
                                  spender,
                                  value,
                                  _permitNonces[owner]++,
                                  deadline
                              )
                          )
                      );
                      require(
                          SignatureChecker.isValidSignatureNow(
                              owner,
                              typedDataHash,
                              signature
                          ),
                          "EIP2612: invalid signature"
                      );
                      _approve(owner, spender, value);
                  }
              }
              /**
               * SPDX-License-Identifier: Apache-2.0
               *
               * Copyright (c) 2023, Circle Internet Financial, LLC.
               *
               * Licensed under the Apache License, Version 2.0 (the "License");
               * you may not use this file except in compliance with the License.
               * You may obtain a copy of the License at
               *
               * http://www.apache.org/licenses/LICENSE-2.0
               *
               * Unless required by applicable law or agreed to in writing, software
               * distributed under the License is distributed on an "AS IS" BASIS,
               * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
               * See the License for the specific language governing permissions and
               * limitations under the License.
               */
              pragma solidity 0.6.12;
              import { AbstractFiatTokenV1 } from "../v1/AbstractFiatTokenV1.sol";
              abstract contract AbstractFiatTokenV2 is AbstractFiatTokenV1 {
                  function _increaseAllowance(
                      address owner,
                      address spender,
                      uint256 increment
                  ) internal virtual;
                  function _decreaseAllowance(
                      address owner,
                      address spender,
                      uint256 decrement
                  ) internal virtual;
              }
              /**
               * SPDX-License-Identifier: MIT
               *
               * Copyright (c) 2016 Smart Contract Solutions, Inc.
               * Copyright (c) 2018-2020 CENTRE SECZ
               *
               * Permission is hereby granted, free of charge, to any person obtaining a copy
               * of this software and associated documentation files (the "Software"), to deal
               * in the Software without restriction, including without limitation the rights
               * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
               * copies of the Software, and to permit persons to whom the Software is
               * furnished to do so, subject to the following conditions:
               *
               * The above copyright notice and this permission notice shall be included in
               * copies or substantial portions of the Software.
               *
               * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
               * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
               * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
               * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
               * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
               * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
               * SOFTWARE.
               */
              pragma solidity 0.6.12;
              import { Ownable } from "./Ownable.sol";
              /**
               * @notice Base contract which allows children to implement an emergency stop
               * mechanism
               * @dev Forked from https://github.com/OpenZeppelin/openzeppelin-contracts/blob/feb665136c0dae9912e08397c1a21c4af3651ef3/contracts/lifecycle/Pausable.sol
               * Modifications:
               * 1. Added pauser role, switched pause/unpause to be onlyPauser (6/14/2018)
               * 2. Removed whenNotPause/whenPaused from pause/unpause (6/14/2018)
               * 3. Removed whenPaused (6/14/2018)
               * 4. Switches ownable library to use ZeppelinOS (7/12/18)
               * 5. Remove constructor (7/13/18)
               * 6. Reformat, conform to Solidity 0.6 syntax and add error messages (5/13/20)
               * 7. Make public functions external (5/27/20)
               */
              contract Pausable is Ownable {
                  event Pause();
                  event Unpause();
                  event PauserChanged(address indexed newAddress);
                  address public pauser;
                  bool public paused = false;
                  /**
                   * @dev Modifier to make a function callable only when the contract is not paused.
                   */
                  modifier whenNotPaused() {
                      require(!paused, "Pausable: paused");
                      _;
                  }
                  /**
                   * @dev throws if called by any account other than the pauser
                   */
                  modifier onlyPauser() {
                      require(msg.sender == pauser, "Pausable: caller is not the pauser");
                      _;
                  }
                  /**
                   * @dev called by the owner to pause, triggers stopped state
                   */
                  function pause() external onlyPauser {
                      paused = true;
                      emit Pause();
                  }
                  /**
                   * @dev called by the owner to unpause, returns to normal state
                   */
                  function unpause() external onlyPauser {
                      paused = false;
                      emit Unpause();
                  }
                  /**
                   * @notice Updates the pauser address.
                   * @param _newPauser The address of the new pauser.
                   */
                  function updatePauser(address _newPauser) external onlyOwner {
                      require(
                          _newPauser != address(0),
                          "Pausable: new pauser is the zero address"
                      );
                      pauser = _newPauser;
                      emit PauserChanged(pauser);
                  }
              }
              /**
               * SPDX-License-Identifier: MIT
               *
               * Copyright (c) 2018 zOS Global Limited.
               * Copyright (c) 2018-2020 CENTRE SECZ
               *
               * Permission is hereby granted, free of charge, to any person obtaining a copy
               * of this software and associated documentation files (the "Software"), to deal
               * in the Software without restriction, including without limitation the rights
               * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
               * copies of the Software, and to permit persons to whom the Software is
               * furnished to do so, subject to the following conditions:
               *
               * The above copyright notice and this permission notice shall be included in
               * copies or substantial portions of the Software.
               *
               * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
               * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
               * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
               * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
               * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
               * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
               * SOFTWARE.
               */
              pragma solidity 0.6.12;
              /**
               * @notice The Ownable contract has an owner address, and provides basic
               * authorization control functions
               * @dev Forked from https://github.com/OpenZeppelin/openzeppelin-labs/blob/3887ab77b8adafba4a26ace002f3a684c1a3388b/upgradeability_ownership/contracts/ownership/Ownable.sol
               * Modifications:
               * 1. Consolidate OwnableStorage into this contract (7/13/18)
               * 2. Reformat, conform to Solidity 0.6 syntax, and add error messages (5/13/20)
               * 3. Make public functions external (5/27/20)
               */
              contract Ownable {
                  // Owner of the contract
                  address private _owner;
                  /**
                   * @dev Event to show ownership has been transferred
                   * @param previousOwner representing the address of the previous owner
                   * @param newOwner representing the address of the new owner
                   */
                  event OwnershipTransferred(address previousOwner, address newOwner);
                  /**
                   * @dev The constructor sets the original owner of the contract to the sender account.
                   */
                  constructor() public {
                      setOwner(msg.sender);
                  }
                  /**
                   * @dev Tells the address of the owner
                   * @return the address of the owner
                   */
                  function owner() external view returns (address) {
                      return _owner;
                  }
                  /**
                   * @dev Sets a new owner address
                   */
                  function setOwner(address newOwner) internal {
                      _owner = newOwner;
                  }
                  /**
                   * @dev Throws if called by any account other than the owner.
                   */
                  modifier onlyOwner() {
                      require(msg.sender == _owner, "Ownable: caller is not the owner");
                      _;
                  }
                  /**
                   * @dev Allows the current owner to transfer control of the contract to a newOwner.
                   * @param newOwner The address to transfer ownership to.
                   */
                  function transferOwnership(address newOwner) external onlyOwner {
                      require(
                          newOwner != address(0),
                          "Ownable: new owner is the zero address"
                      );
                      emit OwnershipTransferred(_owner, newOwner);
                      setOwner(newOwner);
                  }
              }
              /**
               * SPDX-License-Identifier: Apache-2.0
               *
               * Copyright (c) 2023, Circle Internet Financial, LLC.
               *
               * Licensed under the Apache License, Version 2.0 (the "License");
               * you may not use this file except in compliance with the License.
               * You may obtain a copy of the License at
               *
               * http://www.apache.org/licenses/LICENSE-2.0
               *
               * Unless required by applicable law or agreed to in writing, software
               * distributed under the License is distributed on an "AS IS" BASIS,
               * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
               * See the License for the specific language governing permissions and
               * limitations under the License.
               */
              pragma solidity 0.6.12;
              import { SafeMath } from "@openzeppelin/contracts/math/SafeMath.sol";
              import { AbstractFiatTokenV1 } from "./AbstractFiatTokenV1.sol";
              import { Ownable } from "./Ownable.sol";
              import { Pausable } from "./Pausable.sol";
              import { Blacklistable } from "./Blacklistable.sol";
              /**
               * @title FiatToken
               * @dev ERC20 Token backed by fiat reserves
               */
              contract FiatTokenV1 is AbstractFiatTokenV1, Ownable, Pausable, Blacklistable {
                  using SafeMath for uint256;
                  string public name;
                  string public symbol;
                  uint8 public decimals;
                  string public currency;
                  address public masterMinter;
                  bool internal initialized;
                  /// @dev A mapping that stores the balance and blacklist states for a given address.
                  /// The first bit defines whether the address is blacklisted (1 if blacklisted, 0 otherwise).
                  /// The last 255 bits define the balance for the address.
                  mapping(address => uint256) internal balanceAndBlacklistStates;
                  mapping(address => mapping(address => uint256)) internal allowed;
                  uint256 internal totalSupply_ = 0;
                  mapping(address => bool) internal minters;
                  mapping(address => uint256) internal minterAllowed;
                  event Mint(address indexed minter, address indexed to, uint256 amount);
                  event Burn(address indexed burner, uint256 amount);
                  event MinterConfigured(address indexed minter, uint256 minterAllowedAmount);
                  event MinterRemoved(address indexed oldMinter);
                  event MasterMinterChanged(address indexed newMasterMinter);
                  /**
                   * @notice Initializes the fiat token contract.
                   * @param tokenName       The name of the fiat token.
                   * @param tokenSymbol     The symbol of the fiat token.
                   * @param tokenCurrency   The fiat currency that the token represents.
                   * @param tokenDecimals   The number of decimals that the token uses.
                   * @param newMasterMinter The masterMinter address for the fiat token.
                   * @param newPauser       The pauser address for the fiat token.
                   * @param newBlacklister  The blacklister address for the fiat token.
                   * @param newOwner        The owner of the fiat token.
                   */
                  function initialize(
                      string memory tokenName,
                      string memory tokenSymbol,
                      string memory tokenCurrency,
                      uint8 tokenDecimals,
                      address newMasterMinter,
                      address newPauser,
                      address newBlacklister,
                      address newOwner
                  ) public {
                      require(!initialized, "FiatToken: contract is already initialized");
                      require(
                          newMasterMinter != address(0),
                          "FiatToken: new masterMinter is the zero address"
                      );
                      require(
                          newPauser != address(0),
                          "FiatToken: new pauser is the zero address"
                      );
                      require(
                          newBlacklister != address(0),
                          "FiatToken: new blacklister is the zero address"
                      );
                      require(
                          newOwner != address(0),
                          "FiatToken: new owner is the zero address"
                      );
                      name = tokenName;
                      symbol = tokenSymbol;
                      currency = tokenCurrency;
                      decimals = tokenDecimals;
                      masterMinter = newMasterMinter;
                      pauser = newPauser;
                      blacklister = newBlacklister;
                      setOwner(newOwner);
                      initialized = true;
                  }
                  /**
                   * @dev Throws if called by any account other than a minter.
                   */
                  modifier onlyMinters() {
                      require(minters[msg.sender], "FiatToken: caller is not a minter");
                      _;
                  }
                  /**
                   * @notice Mints fiat tokens to an address.
                   * @param _to The address that will receive the minted tokens.
                   * @param _amount The amount of tokens to mint. Must be less than or equal
                   * to the minterAllowance of the caller.
                   * @return True if the operation was successful.
                   */
                  function mint(address _to, uint256 _amount)
                      external
                      whenNotPaused
                      onlyMinters
                      notBlacklisted(msg.sender)
                      notBlacklisted(_to)
                      returns (bool)
                  {
                      require(_to != address(0), "FiatToken: mint to the zero address");
                      require(_amount > 0, "FiatToken: mint amount not greater than 0");
                      uint256 mintingAllowedAmount = minterAllowed[msg.sender];
                      require(
                          _amount <= mintingAllowedAmount,
                          "FiatToken: mint amount exceeds minterAllowance"
                      );
                      totalSupply_ = totalSupply_.add(_amount);
                      _setBalance(_to, _balanceOf(_to).add(_amount));
                      minterAllowed[msg.sender] = mintingAllowedAmount.sub(_amount);
                      emit Mint(msg.sender, _to, _amount);
                      emit Transfer(address(0), _to, _amount);
                      return true;
                  }
                  /**
                   * @dev Throws if called by any account other than the masterMinter
                   */
                  modifier onlyMasterMinter() {
                      require(
                          msg.sender == masterMinter,
                          "FiatToken: caller is not the masterMinter"
                      );
                      _;
                  }
                  /**
                   * @notice Gets the minter allowance for an account.
                   * @param minter The address to check.
                   * @return The remaining minter allowance for the account.
                   */
                  function minterAllowance(address minter) external view returns (uint256) {
                      return minterAllowed[minter];
                  }
                  /**
                   * @notice Checks if an account is a minter.
                   * @param account The address to check.
                   * @return True if the account is a minter, false if the account is not a minter.
                   */
                  function isMinter(address account) external view returns (bool) {
                      return minters[account];
                  }
                  /**
                   * @notice Gets the remaining amount of fiat tokens a spender is allowed to transfer on
                   * behalf of the token owner.
                   * @param owner   The token owner's address.
                   * @param spender The spender's address.
                   * @return The remaining allowance.
                   */
                  function allowance(address owner, address spender)
                      external
                      override
                      view
                      returns (uint256)
                  {
                      return allowed[owner][spender];
                  }
                  /**
                   * @notice Gets the totalSupply of the fiat token.
                   * @return The totalSupply of the fiat token.
                   */
                  function totalSupply() external override view returns (uint256) {
                      return totalSupply_;
                  }
                  /**
                   * @notice Gets the fiat token balance of an account.
                   * @param account  The address to check.
                   * @return balance The fiat token balance of the account.
                   */
                  function balanceOf(address account)
                      external
                      override
                      view
                      returns (uint256)
                  {
                      return _balanceOf(account);
                  }
                  /**
                   * @notice Sets a fiat token allowance for a spender to spend on behalf of the caller.
                   * @param spender The spender's address.
                   * @param value   The allowance amount.
                   * @return True if the operation was successful.
                   */
                  function approve(address spender, uint256 value)
                      external
                      virtual
                      override
                      whenNotPaused
                      notBlacklisted(msg.sender)
                      notBlacklisted(spender)
                      returns (bool)
                  {
                      _approve(msg.sender, spender, value);
                      return true;
                  }
                  /**
                   * @dev Internal function to set allowance.
                   * @param owner     Token owner's address.
                   * @param spender   Spender's address.
                   * @param value     Allowance amount.
                   */
                  function _approve(
                      address owner,
                      address spender,
                      uint256 value
                  ) internal override {
                      require(owner != address(0), "ERC20: approve from the zero address");
                      require(spender != address(0), "ERC20: approve to the zero address");
                      allowed[owner][spender] = value;
                      emit Approval(owner, spender, value);
                  }
                  /**
                   * @notice Transfers tokens from an address to another by spending the caller's allowance.
                   * @dev The caller must have some fiat token allowance on the payer's tokens.
                   * @param from  Payer's address.
                   * @param to    Payee's address.
                   * @param value Transfer amount.
                   * @return True if the operation was successful.
                   */
                  function transferFrom(
                      address from,
                      address to,
                      uint256 value
                  )
                      external
                      override
                      whenNotPaused
                      notBlacklisted(msg.sender)
                      notBlacklisted(from)
                      notBlacklisted(to)
                      returns (bool)
                  {
                      require(
                          value <= allowed[from][msg.sender],
                          "ERC20: transfer amount exceeds allowance"
                      );
                      _transfer(from, to, value);
                      allowed[from][msg.sender] = allowed[from][msg.sender].sub(value);
                      return true;
                  }
                  /**
                   * @notice Transfers tokens from the caller.
                   * @param to    Payee's address.
                   * @param value Transfer amount.
                   * @return True if the operation was successful.
                   */
                  function transfer(address to, uint256 value)
                      external
                      override
                      whenNotPaused
                      notBlacklisted(msg.sender)
                      notBlacklisted(to)
                      returns (bool)
                  {
                      _transfer(msg.sender, to, value);
                      return true;
                  }
                  /**
                   * @dev Internal function to process transfers.
                   * @param from  Payer's address.
                   * @param to    Payee's address.
                   * @param value Transfer amount.
                   */
                  function _transfer(
                      address from,
                      address to,
                      uint256 value
                  ) internal override {
                      require(from != address(0), "ERC20: transfer from the zero address");
                      require(to != address(0), "ERC20: transfer to the zero address");
                      require(
                          value <= _balanceOf(from),
                          "ERC20: transfer amount exceeds balance"
                      );
                      _setBalance(from, _balanceOf(from).sub(value));
                      _setBalance(to, _balanceOf(to).add(value));
                      emit Transfer(from, to, value);
                  }
                  /**
                   * @notice Adds or updates a new minter with a mint allowance.
                   * @param minter The address of the minter.
                   * @param minterAllowedAmount The minting amount allowed for the minter.
                   * @return True if the operation was successful.
                   */
                  function configureMinter(address minter, uint256 minterAllowedAmount)
                      external
                      whenNotPaused
                      onlyMasterMinter
                      returns (bool)
                  {
                      minters[minter] = true;
                      minterAllowed[minter] = minterAllowedAmount;
                      emit MinterConfigured(minter, minterAllowedAmount);
                      return true;
                  }
                  /**
                   * @notice Removes a minter.
                   * @param minter The address of the minter to remove.
                   * @return True if the operation was successful.
                   */
                  function removeMinter(address minter)
                      external
                      onlyMasterMinter
                      returns (bool)
                  {
                      minters[minter] = false;
                      minterAllowed[minter] = 0;
                      emit MinterRemoved(minter);
                      return true;
                  }
                  /**
                   * @notice Allows a minter to burn some of its own tokens.
                   * @dev The caller must be a minter, must not be blacklisted, and the amount to burn
                   * should be less than or equal to the account's balance.
                   * @param _amount the amount of tokens to be burned.
                   */
                  function burn(uint256 _amount)
                      external
                      whenNotPaused
                      onlyMinters
                      notBlacklisted(msg.sender)
                  {
                      uint256 balance = _balanceOf(msg.sender);
                      require(_amount > 0, "FiatToken: burn amount not greater than 0");
                      require(balance >= _amount, "FiatToken: burn amount exceeds balance");
                      totalSupply_ = totalSupply_.sub(_amount);
                      _setBalance(msg.sender, balance.sub(_amount));
                      emit Burn(msg.sender, _amount);
                      emit Transfer(msg.sender, address(0), _amount);
                  }
                  /**
                   * @notice Updates the master minter address.
                   * @param _newMasterMinter The address of the new master minter.
                   */
                  function updateMasterMinter(address _newMasterMinter) external onlyOwner {
                      require(
                          _newMasterMinter != address(0),
                          "FiatToken: new masterMinter is the zero address"
                      );
                      masterMinter = _newMasterMinter;
                      emit MasterMinterChanged(masterMinter);
                  }
                  /**
                   * @inheritdoc Blacklistable
                   */
                  function _blacklist(address _account) internal override {
                      _setBlacklistState(_account, true);
                  }
                  /**
                   * @inheritdoc Blacklistable
                   */
                  function _unBlacklist(address _account) internal override {
                      _setBlacklistState(_account, false);
                  }
                  /**
                   * @dev Helper method that sets the blacklist state of an account.
                   * @param _account         The address of the account.
                   * @param _shouldBlacklist True if the account should be blacklisted, false if the account should be unblacklisted.
                   */
                  function _setBlacklistState(address _account, bool _shouldBlacklist)
                      internal
                      virtual
                  {
                      _deprecatedBlacklisted[_account] = _shouldBlacklist;
                  }
                  /**
                   * @dev Helper method that sets the balance of an account.
                   * @param _account The address of the account.
                   * @param _balance The new fiat token balance of the account.
                   */
                  function _setBalance(address _account, uint256 _balance) internal virtual {
                      balanceAndBlacklistStates[_account] = _balance;
                  }
                  /**
                   * @inheritdoc Blacklistable
                   */
                  function _isBlacklisted(address _account)
                      internal
                      virtual
                      override
                      view
                      returns (bool)
                  {
                      return _deprecatedBlacklisted[_account];
                  }
                  /**
                   * @dev Helper method to obtain the balance of an account.
                   * @param _account  The address of the account.
                   * @return          The fiat token balance of the account.
                   */
                  function _balanceOf(address _account)
                      internal
                      virtual
                      view
                      returns (uint256)
                  {
                      return balanceAndBlacklistStates[_account];
                  }
              }
              /**
               * SPDX-License-Identifier: Apache-2.0
               *
               * Copyright (c) 2023, Circle Internet Financial, LLC.
               *
               * Licensed under the Apache License, Version 2.0 (the "License");
               * you may not use this file except in compliance with the License.
               * You may obtain a copy of the License at
               *
               * http://www.apache.org/licenses/LICENSE-2.0
               *
               * Unless required by applicable law or agreed to in writing, software
               * distributed under the License is distributed on an "AS IS" BASIS,
               * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
               * See the License for the specific language governing permissions and
               * limitations under the License.
               */
              pragma solidity 0.6.12;
              import { Ownable } from "./Ownable.sol";
              /**
               * @title Blacklistable Token
               * @dev Allows accounts to be blacklisted by a "blacklister" role
               */
              abstract contract Blacklistable is Ownable {
                  address public blacklister;
                  mapping(address => bool) internal _deprecatedBlacklisted;
                  event Blacklisted(address indexed _account);
                  event UnBlacklisted(address indexed _account);
                  event BlacklisterChanged(address indexed newBlacklister);
                  /**
                   * @dev Throws if called by any account other than the blacklister.
                   */
                  modifier onlyBlacklister() {
                      require(
                          msg.sender == blacklister,
                          "Blacklistable: caller is not the blacklister"
                      );
                      _;
                  }
                  /**
                   * @dev Throws if argument account is blacklisted.
                   * @param _account The address to check.
                   */
                  modifier notBlacklisted(address _account) {
                      require(
                          !_isBlacklisted(_account),
                          "Blacklistable: account is blacklisted"
                      );
                      _;
                  }
                  /**
                   * @notice Checks if account is blacklisted.
                   * @param _account The address to check.
                   * @return True if the account is blacklisted, false if the account is not blacklisted.
                   */
                  function isBlacklisted(address _account) external view returns (bool) {
                      return _isBlacklisted(_account);
                  }
                  /**
                   * @notice Adds account to blacklist.
                   * @param _account The address to blacklist.
                   */
                  function blacklist(address _account) external onlyBlacklister {
                      _blacklist(_account);
                      emit Blacklisted(_account);
                  }
                  /**
                   * @notice Removes account from blacklist.
                   * @param _account The address to remove from the blacklist.
                   */
                  function unBlacklist(address _account) external onlyBlacklister {
                      _unBlacklist(_account);
                      emit UnBlacklisted(_account);
                  }
                  /**
                   * @notice Updates the blacklister address.
                   * @param _newBlacklister The address of the new blacklister.
                   */
                  function updateBlacklister(address _newBlacklister) external onlyOwner {
                      require(
                          _newBlacklister != address(0),
                          "Blacklistable: new blacklister is the zero address"
                      );
                      blacklister = _newBlacklister;
                      emit BlacklisterChanged(blacklister);
                  }
                  /**
                   * @dev Checks if account is blacklisted.
                   * @param _account The address to check.
                   * @return true if the account is blacklisted, false otherwise.
                   */
                  function _isBlacklisted(address _account)
                      internal
                      virtual
                      view
                      returns (bool);
                  /**
                   * @dev Helper method that blacklists an account.
                   * @param _account The address to blacklist.
                   */
                  function _blacklist(address _account) internal virtual;
                  /**
                   * @dev Helper method that unblacklists an account.
                   * @param _account The address to unblacklist.
                   */
                  function _unBlacklist(address _account) internal virtual;
              }
              /**
               * SPDX-License-Identifier: Apache-2.0
               *
               * Copyright (c) 2023, Circle Internet Financial, LLC.
               *
               * Licensed under the Apache License, Version 2.0 (the "License");
               * you may not use this file except in compliance with the License.
               * You may obtain a copy of the License at
               *
               * http://www.apache.org/licenses/LICENSE-2.0
               *
               * Unless required by applicable law or agreed to in writing, software
               * distributed under the License is distributed on an "AS IS" BASIS,
               * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
               * See the License for the specific language governing permissions and
               * limitations under the License.
               */
              pragma solidity 0.6.12;
              import { IERC20 } from "@openzeppelin/contracts/token/ERC20/IERC20.sol";
              abstract contract AbstractFiatTokenV1 is IERC20 {
                  function _approve(
                      address owner,
                      address spender,
                      uint256 value
                  ) internal virtual;
                  function _transfer(
                      address from,
                      address to,
                      uint256 value
                  ) internal virtual;
              }
              /**
               * SPDX-License-Identifier: Apache-2.0
               *
               * Copyright (c) 2023, Circle Internet Financial, LLC.
               *
               * Licensed under the Apache License, Version 2.0 (the "License");
               * you may not use this file except in compliance with the License.
               * You may obtain a copy of the License at
               *
               * http://www.apache.org/licenses/LICENSE-2.0
               *
               * Unless required by applicable law or agreed to in writing, software
               * distributed under the License is distributed on an "AS IS" BASIS,
               * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
               * See the License for the specific language governing permissions and
               * limitations under the License.
               */
              pragma solidity 0.6.12;
              import { Ownable } from "../v1/Ownable.sol";
              import { IERC20 } from "@openzeppelin/contracts/token/ERC20/IERC20.sol";
              import { SafeERC20 } from "@openzeppelin/contracts/token/ERC20/SafeERC20.sol";
              contract Rescuable is Ownable {
                  using SafeERC20 for IERC20;
                  address private _rescuer;
                  event RescuerChanged(address indexed newRescuer);
                  /**
                   * @notice Returns current rescuer
                   * @return Rescuer's address
                   */
                  function rescuer() external view returns (address) {
                      return _rescuer;
                  }
                  /**
                   * @notice Revert if called by any account other than the rescuer.
                   */
                  modifier onlyRescuer() {
                      require(msg.sender == _rescuer, "Rescuable: caller is not the rescuer");
                      _;
                  }
                  /**
                   * @notice Rescue ERC20 tokens locked up in this contract.
                   * @param tokenContract ERC20 token contract address
                   * @param to        Recipient address
                   * @param amount    Amount to withdraw
                   */
                  function rescueERC20(
                      IERC20 tokenContract,
                      address to,
                      uint256 amount
                  ) external onlyRescuer {
                      tokenContract.safeTransfer(to, amount);
                  }
                  /**
                   * @notice Updates the rescuer address.
                   * @param newRescuer The address of the new rescuer.
                   */
                  function updateRescuer(address newRescuer) external onlyOwner {
                      require(
                          newRescuer != address(0),
                          "Rescuable: new rescuer is the zero address"
                      );
                      _rescuer = newRescuer;
                      emit RescuerChanged(newRescuer);
                  }
              }
              /**
               * SPDX-License-Identifier: Apache-2.0
               *
               * Copyright (c) 2023, Circle Internet Financial, LLC.
               *
               * Licensed under the Apache License, Version 2.0 (the "License");
               * you may not use this file except in compliance with the License.
               * You may obtain a copy of the License at
               *
               * http://www.apache.org/licenses/LICENSE-2.0
               *
               * Unless required by applicable law or agreed to in writing, software
               * distributed under the License is distributed on an "AS IS" BASIS,
               * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
               * See the License for the specific language governing permissions and
               * limitations under the License.
               */
              pragma solidity 0.6.12;
              import { FiatTokenV1 } from "../v1/FiatTokenV1.sol";
              import { Rescuable } from "./Rescuable.sol";
              /**
               * @title FiatTokenV1_1
               * @dev ERC20 Token backed by fiat reserves
               */
              contract FiatTokenV1_1 is FiatTokenV1, Rescuable {
              }
              /**
               * SPDX-License-Identifier: Apache-2.0
               *
               * Copyright (c) 2023, Circle Internet Financial, LLC.
               *
               * Licensed under the Apache License, Version 2.0 (the "License");
               * you may not use this file except in compliance with the License.
               * You may obtain a copy of the License at
               *
               * http://www.apache.org/licenses/LICENSE-2.0
               *
               * Unless required by applicable law or agreed to in writing, software
               * distributed under the License is distributed on an "AS IS" BASIS,
               * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
               * See the License for the specific language governing permissions and
               * limitations under the License.
               */
              pragma solidity 0.6.12;
              import { ECRecover } from "./ECRecover.sol";
              import { IERC1271 } from "../interface/IERC1271.sol";
              /**
               * @dev Signature verification helper that can be used instead of `ECRecover.recover` to seamlessly support both ECDSA
               * signatures from externally owned accounts (EOAs) as well as ERC1271 signatures from smart contract wallets.
               *
               * Adapted from https://github.com/OpenZeppelin/openzeppelin-contracts/blob/21bb89ef5bfc789b9333eb05e3ba2b7b284ac77c/contracts/utils/cryptography/SignatureChecker.sol
               */
              library SignatureChecker {
                  /**
                   * @dev Checks if a signature is valid for a given signer and data hash. If the signer is a smart contract, the
                   * signature is validated against that smart contract using ERC1271, otherwise it's validated using `ECRecover.recover`.
                   * @param signer        Address of the claimed signer
                   * @param digest        Keccak-256 hash digest of the signed message
                   * @param signature     Signature byte array associated with hash
                   */
                  function isValidSignatureNow(
                      address signer,
                      bytes32 digest,
                      bytes memory signature
                  ) external view returns (bool) {
                      if (!isContract(signer)) {
                          return ECRecover.recover(digest, signature) == signer;
                      }
                      return isValidERC1271SignatureNow(signer, digest, signature);
                  }
                  /**
                   * @dev Checks if a signature is valid for a given signer and data hash. The signature is validated
                   * against the signer smart contract using ERC1271.
                   * @param signer        Address of the claimed signer
                   * @param digest        Keccak-256 hash digest of the signed message
                   * @param signature     Signature byte array associated with hash
                   *
                   * NOTE: Unlike ECDSA signatures, contract signatures are revocable, and the outcome of this function can thus
                   * change through time. It could return true at block N and false at block N+1 (or the opposite).
                   */
                  function isValidERC1271SignatureNow(
                      address signer,
                      bytes32 digest,
                      bytes memory signature
                  ) internal view returns (bool) {
                      (bool success, bytes memory result) = signer.staticcall(
                          abi.encodeWithSelector(
                              IERC1271.isValidSignature.selector,
                              digest,
                              signature
                          )
                      );
                      return (success &&
                          result.length >= 32 &&
                          abi.decode(result, (bytes32)) ==
                          bytes32(IERC1271.isValidSignature.selector));
                  }
                  /**
                   * @dev Checks if the input address is a smart contract.
                   */
                  function isContract(address addr) internal view returns (bool) {
                      uint256 size;
                      assembly {
                          size := extcodesize(addr)
                      }
                      return size > 0;
                  }
              }
              /**
               * SPDX-License-Identifier: Apache-2.0
               *
               * Copyright (c) 2023, Circle Internet Financial, LLC.
               *
               * Licensed under the Apache License, Version 2.0 (the "License");
               * you may not use this file except in compliance with the License.
               * You may obtain a copy of the License at
               *
               * http://www.apache.org/licenses/LICENSE-2.0
               *
               * Unless required by applicable law or agreed to in writing, software
               * distributed under the License is distributed on an "AS IS" BASIS,
               * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
               * See the License for the specific language governing permissions and
               * limitations under the License.
               */
              pragma solidity 0.6.12;
              /**
               * @dev Signature message hash utilities for producing digests to be consumed by {ECDSA} recovery or signing.
               *
               * The library provides methods for generating a hash of a message that conforms to the
               * https://eips.ethereum.org/EIPS/eip-191[EIP 191] and https://eips.ethereum.org/EIPS/eip-712[EIP 712]
               * specifications.
               */
              library MessageHashUtils {
                  /**
                   * @dev Returns the keccak256 digest of an EIP-712 typed data (EIP-191 version `0x01`).
                   * Adapted from https://github.com/OpenZeppelin/openzeppelin-contracts/blob/21bb89ef5bfc789b9333eb05e3ba2b7b284ac77c/contracts/utils/cryptography/MessageHashUtils.sol
                   *
                   * The digest is calculated from a `domainSeparator` and a `structHash`, by prefixing them with
                   * `\\x19\\x01` and hashing the result. It corresponds to the hash signed by the
                   * https://eips.ethereum.org/EIPS/eip-712[`eth_signTypedData`] JSON-RPC method as part of EIP-712.
                   *
                   * @param domainSeparator    Domain separator
                   * @param structHash         Hashed EIP-712 data struct
                   * @return digest            The keccak256 digest of an EIP-712 typed data
                   */
                  function toTypedDataHash(bytes32 domainSeparator, bytes32 structHash)
                      internal
                      pure
                      returns (bytes32 digest)
                  {
                      assembly {
                          let ptr := mload(0x40)
                          mstore(ptr, "\\x19\\x01")
                          mstore(add(ptr, 0x02), domainSeparator)
                          mstore(add(ptr, 0x22), structHash)
                          digest := keccak256(ptr, 0x42)
                      }
                  }
              }
              /**
               * SPDX-License-Identifier: Apache-2.0
               *
               * Copyright (c) 2023, Circle Internet Financial, LLC.
               *
               * Licensed under the Apache License, Version 2.0 (the "License");
               * you may not use this file except in compliance with the License.
               * You may obtain a copy of the License at
               *
               * http://www.apache.org/licenses/LICENSE-2.0
               *
               * Unless required by applicable law or agreed to in writing, software
               * distributed under the License is distributed on an "AS IS" BASIS,
               * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
               * See the License for the specific language governing permissions and
               * limitations under the License.
               */
              pragma solidity 0.6.12;
              /**
               * @title EIP712
               * @notice A library that provides EIP712 helper functions
               */
              library EIP712 {
                  /**
                   * @notice Make EIP712 domain separator
                   * @param name      Contract name
                   * @param version   Contract version
                   * @param chainId   Blockchain ID
                   * @return Domain separator
                   */
                  function makeDomainSeparator(
                      string memory name,
                      string memory version,
                      uint256 chainId
                  ) internal view returns (bytes32) {
                      return
                          keccak256(
                              abi.encode(
                                  // keccak256("EIP712Domain(string name,string version,uint256 chainId,address verifyingContract)")
                                  0x8b73c3c69bb8fe3d512ecc4cf759cc79239f7b179b0ffacaa9a75d522b39400f,
                                  keccak256(bytes(name)),
                                  keccak256(bytes(version)),
                                  chainId,
                                  address(this)
                              )
                          );
                  }
                  /**
                   * @notice Make EIP712 domain separator
                   * @param name      Contract name
                   * @param version   Contract version
                   * @return Domain separator
                   */
                  function makeDomainSeparator(string memory name, string memory version)
                      internal
                      view
                      returns (bytes32)
                  {
                      uint256 chainId;
                      assembly {
                          chainId := chainid()
                      }
                      return makeDomainSeparator(name, version, chainId);
                  }
              }
              /**
               * SPDX-License-Identifier: Apache-2.0
               *
               * Copyright (c) 2023, Circle Internet Financial, LLC.
               *
               * Licensed under the Apache License, Version 2.0 (the "License");
               * you may not use this file except in compliance with the License.
               * You may obtain a copy of the License at
               *
               * http://www.apache.org/licenses/LICENSE-2.0
               *
               * Unless required by applicable law or agreed to in writing, software
               * distributed under the License is distributed on an "AS IS" BASIS,
               * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
               * See the License for the specific language governing permissions and
               * limitations under the License.
               */
              pragma solidity 0.6.12;
              /**
               * @title ECRecover
               * @notice A library that provides a safe ECDSA recovery function
               */
              library ECRecover {
                  /**
                   * @notice Recover signer's address from a signed message
                   * @dev Adapted from: https://github.com/OpenZeppelin/openzeppelin-contracts/blob/65e4ffde586ec89af3b7e9140bdc9235d1254853/contracts/cryptography/ECDSA.sol
                   * Modifications: Accept v, r, and s as separate arguments
                   * @param digest    Keccak-256 hash digest of the signed message
                   * @param v         v of the signature
                   * @param r         r of the signature
                   * @param s         s of the signature
                   * @return Signer address
                   */
                  function recover(
                      bytes32 digest,
                      uint8 v,
                      bytes32 r,
                      bytes32 s
                  ) internal pure returns (address) {
                      // EIP-2 still allows signature malleability for ecrecover(). Remove this possibility and make the signature
                      // unique. Appendix F in the Ethereum Yellow paper (https://ethereum.github.io/yellowpaper/paper.pdf), defines
                      // the valid range for s in (281): 0 < s < secp256k1n ÷ 2 + 1, and for v in (282): v ∈ {27, 28}. Most
                      // signatures from current libraries generate a unique signature with an s-value in the lower half order.
                      //
                      // If your library generates malleable signatures, such as s-values in the upper range, calculate a new s-value
                      // with 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEBAAEDCE6AF48A03BBFD25E8CD0364141 - s1 and flip v from 27 to 28 or
                      // vice versa. If your library also generates signatures with 0/1 for v instead 27/28, add 27 to v to accept
                      // these malleable signatures as well.
                      if (
                          uint256(s) >
                          0x7FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF5D576E7357A4501DDFE92F46681B20A0
                      ) {
                          revert("ECRecover: invalid signature 's' value");
                      }
                      if (v != 27 && v != 28) {
                          revert("ECRecover: invalid signature 'v' value");
                      }
                      // If the signature is valid (and not malleable), return the signer address
                      address signer = ecrecover(digest, v, r, s);
                      require(signer != address(0), "ECRecover: invalid signature");
                      return signer;
                  }
                  /**
                   * @notice Recover signer's address from a signed message
                   * @dev Adapted from: https://github.com/OpenZeppelin/openzeppelin-contracts/blob/0053ee040a7ff1dbc39691c9e67a69f564930a88/contracts/utils/cryptography/ECDSA.sol
                   * @param digest    Keccak-256 hash digest of the signed message
                   * @param signature Signature byte array associated with hash
                   * @return Signer address
                   */
                  function recover(bytes32 digest, bytes memory signature)
                      internal
                      pure
                      returns (address)
                  {
                      require(signature.length == 65, "ECRecover: invalid signature length");
                      bytes32 r;
                      bytes32 s;
                      uint8 v;
                      // ecrecover takes the signature parameters, and the only way to get them
                      // currently is to use assembly.
                      /// @solidity memory-safe-assembly
                      assembly {
                          r := mload(add(signature, 0x20))
                          s := mload(add(signature, 0x40))
                          v := byte(0, mload(add(signature, 0x60)))
                      }
                      return recover(digest, v, r, s);
                  }
              }
              /**
               * SPDX-License-Identifier: Apache-2.0
               *
               * Copyright (c) 2023, Circle Internet Financial, LLC.
               *
               * Licensed under the Apache License, Version 2.0 (the "License");
               * you may not use this file except in compliance with the License.
               * You may obtain a copy of the License at
               *
               * http://www.apache.org/licenses/LICENSE-2.0
               *
               * Unless required by applicable law or agreed to in writing, software
               * distributed under the License is distributed on an "AS IS" BASIS,
               * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
               * See the License for the specific language governing permissions and
               * limitations under the License.
               */
              pragma solidity 0.6.12;
              /**
               * @dev Interface of the ERC1271 standard signature validation method for
               * contracts as defined in https://eips.ethereum.org/EIPS/eip-1271[ERC-1271].
               */
              interface IERC1271 {
                  /**
                   * @dev Should return whether the signature provided is valid for the provided data
                   * @param hash          Hash of the data to be signed
                   * @param signature     Signature byte array associated with the provided data hash
                   * @return magicValue   bytes4 magic value 0x1626ba7e when function passes
                   */
                  function isValidSignature(bytes32 hash, bytes memory signature)
                      external
                      view
                      returns (bytes4 magicValue);
              }