interface IERC721MandatoryTokenReceiver {
    function onERC721BatchReceived(
        address operator,
        address from,
        uint256[] calldata ids,
        bytes calldata data
    ) external returns (bytes4); // needs to return 0x4b808c46

    function onERC721Received(
        address operator,
        address from,
        uint256 tokenId,
        bytes calldata data
    ) external returns (bytes4); // needs to return 0x150b7a02

    // needs to implements EIP-165
    // function supportsInterface(bytes4 interfaceId)
    //     external
    //     view
    //     returns (bool);
}
/// @dev Note: The ERC-165 identifier for this interface is 0x5e8bf644.
function onERC721Received(
        address operator,
        address from,
        uint256 tokenId,
        bytes calldata data
    ) external returns (bytes4);
// needs to return 0x4b808c46