fix static type annotations #81

	name: Lint

	on: [push, pull_request]

	jobs:
	lint:
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v3
	- name: Setup python 3.9
	uses: actions/setup-python@v2
	with:
	python-version: "3.9"
	- name: Check format
	uses: psf/black@stable
	with:
	options: "--check --diff"
	src: "src"
	- name: Pip install test
	run: \|
	which python
	python -m pip install --upgrade pip wheel
	pip install --user ".[test]"
	- name: Static analysis
	run: mypy .

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