pragma solidity ^0.4.24;

import "zos-lib/contracts/Initializable.sol";
import "./IERC721Receiver.sol";


contract ERC721Holder is Initializable, IERC721Receiver {
  function onERC721Received(
    address,
    address,
    uint256,
    bytes
  )
    public
    returns(bytes4)
  {
    return this.onERC721Received.selector;
  }

  uint256[50] private ______gap;
}