```\nfunction isContract(address account) internal view returns (bool) {\n    // According to EIP-1052, 0x0 is the value returned for not-yet created accounts\n    // and 0xc5d2460186f7233c927e7db2dcc703c0e500b653ca82273b7bfad8045d85a470 is returned\n    // for accounts without code, i.e. `keccak256('')`\n    bytes32 codehash;\n    bytes32 accountHash = 0xc5d2460186f7233c927e7db2dcc703c0e500b653ca82273b7bfad8045d85a470;\n    // solhint-disable-next-line no-inline-assembly\n    assembly {\n        codehash := extcodehash(account)\n    }\n    return (codehash != accountHash && codehash != 0x0);\n}\n```\n