Auto-detect python version and require at least Python 3.9 #11

	name: Python modules

	on:
	push:
	branches: ["main", "devel"]
	pull_request:
	branches: ["main", "devel"]

	permissions:
	contents: read

	jobs:
	test:
	strategy:
	fail-fast: false
	matrix:
	os: [ubuntu-latest, windows-latest, macos-latest]
	python-version: ["3.9", "3.10", "3.11"]
	runs-on: ${{ matrix.os }}

	steps:
	- uses: actions/checkout@v3
	- name: Set up Python 3.10
	uses: actions/setup-python@v3
	with:
	python-version: ${{ matrix.python-version }}
	- uses: actions/cache@v3
	id: cache
	with:
	path: ~/.cache/pip
	key: ${{ runner.os }}-pip-${{ hashFiles('*/requirements.') }}
	restore-keys: \|
	${{ runner.os }}-pip-
	- name: Install dependencies
	run: \|
	python -m pip install --upgrade pip
	pip install pytest
	pip install -r partcad/requirements.txt
	# pip install -r partcad-cli/requirements.txt
	- name: Test with pytest
	env:
	PYTHONPATH: partcad/src
	run: \|
	pytest

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