Refactors #206

	# Install Poetry, dependencies, run tests with a range of Python versions on Ubuntu Linux

	name: Python package

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

	jobs:
	build:

	runs-on: ubuntu-latest
	strategy:
	fail-fast: false
	matrix:
	python-version: ["3.9", "3.10", "3.11", "3.12", "3.13"]

	steps:
	- name: Check out repository
	uses: actions/checkout@v4
	- name: Set up Python ${{ matrix.python-version }}
	uses: actions/setup-python@v5
	with:
	python-version: ${{ matrix.python-version }}
	- name: Install Poetry
	uses: snok/install-poetry@v1
	with:
	virtualenvs-create: true
	virtualenvs-in-project: true
	- name: Install project
	run: poetry install
	- name: Lint imports with isort
	# Use command line due to bugs/docs gaps with official `isort/isort-action`.
	# Exit with error if the code is not properly formatted; show diffs;
	# `black` compatibility.
	# Only target files in `spond` and `test` due to unreliable behaviour on files in
	# root directory.
	# Diffs reported for these files should be the same as fixes made by running
	# `isort .` in the root project folder, which picks up config from
	# `pyproject.toml`.
	run: \|
	source $VENV
	isort spond --check-only --diff --profile black
	isort tests --check-only --diff --profile black
	- name: Lint with black
	# by default: exit with error if the code is not properly formatted; show diffs
	uses: psf/black@stable
	- name: Test with pytest
	run: \|
	source $VENV
	pytest

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