Summary

The .python-version file should be included in version control to help contributors develop with the minimum supported Python version.

Current Situation

• .python-version is ignored by .gitignore
• pyproject.toml specifies requires-python = ">=3.9.2"

Proposed Change

Remove .python-version from .gitignore and commit it with content 3.9.

Benefits

Since the package is actively developed by both the owner and contributors, having .python-version set to the minimum supported version (3.9) ensures contributors automatically develop against the baseline version. This prevents compatibility issues that might be overlooked when developing on newer Python versions, as contributors will catch potential compatibility problems early in their development workflow.

Tools like pyenv will automatically switch to Python 3.9 when entering the project directory, making the setup seamless.

Does this sound like a good idea, @igorbenav? If so, let me know and I can go ahead and submit a PR for this change.