Major update on solvers: #196

	name: Unit tests

	on: [push, workflow_call]

	jobs:
	build:
	runs-on: ubuntu-latest
	strategy:
	matrix:
	python-version: ["3.7", "3.8", "3.9", "3.10", "3.11"]

	steps:
	- uses: actions/checkout@v3
	- 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
	sudo apt-get install libsuitesparse-dev
	if [ -f tests/requirements.txt ]; then pip install -r tests/requirements.txt; fi
	pip install .
	- name: Display Python, pip, setuptools, and all installed versions
	run: \|
	python -c "import sys; print(f'Python {sys.version}')"
	python -c "import pip; print(f'pip {pip.__version__}')"
	python -c "import setuptools; print(f'setuptools {setuptools.__version__}')"
	python -m pip freeze
	- 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 tests

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