struct Data {
    uint256 sellTokenIndex;
    uint256 buyTokenIndex;
    address receiver;
    uint256 sellAmount;
    uint256 buyAmount;
    uint32 validTo;
    bytes32 appData;
    uint256 feeAmount;
    uint256 flags;
    uint256 executedAmount;
    bytes signature;
}

function extractOrder(
    Data calldata trade,
    IERC20[] calldata tokens
) internal pure returns (
    GPv2Order.Data memory order,
    GPv2Signing.Scheme signingScheme
);

function extractFlags(
    uint256 flags
) internal pure returns (
    bytes32 kind,
    bool partiallyFillable,
    bytes32 sellTokenBalance,
    bytes32 buyTokenBalance,
    GPv2Signing.Scheme signingScheme
);