The Python statistics module is a built-in module for performing simple statistical calculations. Since it's part of the standard Python library, it's available in every Python installation. To access ...

os.path.join (folder, filename) ensures the path is correct for the system. On Windows, it uses backslashes (reports\summary.txt); on Linux and macOS it uses forward slashes (reports/summary.txt).

All without needing to worry about writing an HTTP server or complicated request handling logic.