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/*
The MIT License (MIT)
Copyright (c) 2016 Smart Contract Solutions, Inc.
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 ^0.4.23;
/**
* @title ERC721 token receiver interface
* @dev Interface for any contract that wants to support safeTransfers
* rom ERC721 asset contracts.
* Modified from https://github.com/OpenZeppelin/zeppelin-solidity/blob/master/contracts/token/ERC721/ERC721Receiver.sol
*/
contract IERC721Receiver {
/**
* @dev Magic value to be returned upon successful reception of an NFT
* Equals to `bytes4(keccak256("onERC721Received(address,uint256,bytes)"))`,
* which can be also obtained as `ERC721Receiver(0).onERC721Received.selector`
*/
bytes4 constant ERC721_RECEIVED = 0xf0b9e5ba;
/**
* @notice Handle the receipt of an NFT
* @dev The ERC721 smart contract calls this function on the recipient
* after a `safetransfer`. This function MAY throw to revert and reject the
* transfer. This function MUST use 50,000 gas or less. Return of other
* than the magic value MUST result in the transaction being reverted.
* Note: the contract address is always the message sender.
* @param _from The sending address
* @param _tokenId The NFT identifier which is being transfered
* @param _data Additional data with no specified format
* @return `bytes4(keccak256("onERC721Received(address,uint256,bytes)"))`
*/
function onERC721Received(
address _from,
uint256 _tokenId,
bytes _data)
public
returns (bytes4);
}
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