Tinker is now in private beta. Organizations can apply for access, which will be free for the first few weeks.

Claim your complimentary copy worth $21 for free, before the offer ends on Oct 7.

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).