Add type annotations #10

	name: Black formatting

	on: [pull_request, workflow_dispatch]

	jobs:
	black_format:

	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v3
	- name: Set up Python 3.10
	uses: actions/setup-python@v4
	with:
	python-version: "3.10"
	- name: Install dependencies
	run: \|
	python -m pip install --upgrade pip
	pip install -r requirements-dev.txt
	- name: Check files using the black formatter
	run: \|
	black --version
	black --check interpax/ tests/ \|\| black_return_code=$?
	echo "BLACK_RETURN_CODE=$black_return_code" >> $GITHUB_ENV
	black interpax/ tests/
	- name: Annotate diff changes using reviewdog
	uses: reviewdog/action-suggester@v1
	with:
	tool_name: blackfmt
	- name: Fail if not formatted
	run: \|
	exit ${{ env.BLACK_RETURN_CODE }}

Provide feedback