Securely install the latest mypy release from PyPI.

This action installs a pinned version of mypy and all its dependencies, making sure that file hashes match. Pinning your dependencies:

1. Stops software supply chain attacks.
2. Makes sure your CI does not break unexpectedly.

In your GitHub Actions workflow, use this action like so:

      - name: Install mypy from PyPI
        uses: install-pinned/mypy@aa87a0726f32f727c6b94946a614c9f2f90e3d5f  # 1.13.0

You can set up Dependabot so that your pins are updated regularly.

This action is a relatively simple wrapper around poetry and is most useful if there is no existing requirements.txt/poetry.lock/... infrastructure in place. If you already pin all your dependencies in a single place, you don't need it!

See the @install-pinned README for details.