Warning: SPDX license identifier not provided in source file
问题 I created a new solidity contract. The contract is up and running but giving me this warning. Warning: SPDX license identifier not provided in source file. Before publishing, consider adding a comment containing "SPDX-License-Identifier: <SPDX-License>" to each source file. Use "SPDX-License-Identifier: UNLICENSED" for non-open-source code. Please see https://spdx.org for more information. There are no errors while compilation. The Compiler version I am using in https://remix.ethereum.org/ is