# Development

If you want to contribute anything to parso, just open an issue or pull request to discuss it. We welcome changes! Please check the `CONTRIBUTING.md` file in the repository, first.

## Deprecations Process

The deprecation process is as follows:

1. A deprecation is announced in the next major/minor release.

2. We wait either at least a year & at least two minor releases until we remove the deprecated functionality.

## Testing

The test suite depends on `pytest`:

    pip install pytest

To run the tests use the following:

    pytest

If you want to test only a specific Python version (e.g. Python 3.9), it’s as easy as:

    python3.9 -m pytest

Tests are also run automatically on Travis CI.