// SPDX-License-Identifier: MIT // OpenZeppelin Contracts v4.4.1 (token/ERC721/utils/ERC721Holder.sol) pragma solidity ^0.8.0; import "../IERC721Receiver.sol"; /** * @dev Implementation of the {IERC721Receiver} interface. * * Accepts all token transfers. * Make sure the contract is able to use its token with {IERC721-safeTransferFrom}, {IERC721-approve} or {IERC721-setApprovalForAll}. */ contract ERC721Holder is IERC721Receiver { /** * @dev See {IERC721Receiver-onERC721Received}. * * Always returns `IERC721Receiver.onERC721Received.selector`. */ function onERC721Received(address, address, uint256, bytes memory) public virtual override returns (bytes4) { return this.onERC721Received.selector; } }