add type annotations #7

	name: Python tests

	on: [push, pull_request]

	jobs:
	build:
	strategy:
	fail-fast: false
	matrix:
	platform: [windows-latest, macos-latest, ubuntu-latest]
	include:
	- platform: ubuntu-latest
	INSTALL_DEPS: sudo apt-get install libeigen3-dev
	- platform: macos-latest
	INSTALL_DEPS: brew install eigen
	python-version: ["3.7", "3.8", "3.9", "3.10", "3.11", "3.12"]
	runs-on: ${{ matrix.platform }}

	steps:
	- uses: actions/checkout@v4
	- name: Set up Python ${{ matrix.python-version }}
	uses: actions/setup-python@v4
	with:
	python-version: ${{ matrix.python-version }}
	- name: Install dependencies
	run: \|
	python -m pip install --upgrade pip
	pip install flake8 pytest
	pip install -e .
	- name: Lint with flake8
	run: \|
	# stop the build if there are Python syntax errors or undefined names
	flake8 . --count --select=E9,F63,F7,F82 --show-source --statistics
	# exit-zero treats all errors as warnings. The GitHub editor is 127 chars wide
	flake8 . --count --exit-zero --max-complexity=10 --max-line-length=127 --statistics
	- name: Test with pytest
	run: \|
	pytest -v

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