Update Python minimum version to 3.9 #161

	# This workflow will install Python dependencies, run tests and lint with a variety of Python versions
	# For more information see: https://help.github.com/actions/language-and-framework-guides/using-python-with-github-actions

	name: Python package

	on:
	push:
	branches: [ master, 'version_*' ]
	pull_request:
	branches: [ master, 'version_*' ]

	jobs:
	build:

	runs-on: ubuntu-latest
	strategy:
	matrix:
	python-version: ['3.9', '3.10', '3.11', '3.12']

	steps:
	- uses: actions/checkout@v2
	- name: Set up Python ${{ matrix.python-version }}
	uses: actions/setup-python@v2
	with:
	python-version: ${{ matrix.python-version }}
	- name: Install dependencies
	run: \|
	python -m pip install --user pipx
	python -m pipx ensurepath
	pipx install poetry
	poetry install
	- name: Lint with flake8
	run: \|
	# stop the build if there are Python syntax errors or undefined names
	poetry run flake8 . --count --select=E9,F63,F7,F82 --show-source --statistics --ignore=E203,W503
	# exit-zero treats all errors as warnings. The GitHub editor is 127 chars wide
	poetry run flake8 . --count --exit-zero --max-complexity=10 --max-line-length=127 --statistics
	- name: Check black formatter was run
	run: \|
	poetry run black .
	- name: Check type hints with mypy
	run: \|
	poetry run mypy --ignore-missing-imports .
	- name: Run tests and check coverage
	run: \|
	# Fail if total coverage is below 95%
	poetry run pytest --cov=. --cov-fail-under=95 tests/

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