ERC-721 interface 소스 코드 pragma solidity ^0.4.20; /// @title ERC-721 Non-Fungible Token Standard /// @dev See https://eips.ethereum.org/EIPS/eip-721 /// Note: the ERC-165 identifier for this interface is 0x80ac58cd. interface ERC721 /* is ERC165 */ { event Transfer(address indexed _from, address indexed _to, uint256 indexed _tokenId); event Approval(address indexed _owner, address indexed _approv..