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.
--> model_checker_engine_none/input.sol

Warning: Source file does not specify required compiler version!
--> model_checker_engine_none/input.sol