Bump actions/checkout from 3 to 4 #31

	name: Python unit tests
	on: [push, pull_request]
	jobs:
	run-tests:
	runs-on: "ubuntu-20.04"
	steps:
	- uses: actions/checkout@v4
	- name: "Set up Python 3.9"
	uses: actions/setup-python@v3
	with:
	python-version: 3.9
	- name: Install dependencies
	run: pip install -e .
	- name: Run tests with Pytest
	run: python setup.py test
	- name: Upload coverage report to codecov
	if: ${{ success() }}
	run: \|
	pip install codecov
	codecov

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