Lazy open output files, and always close them #278

	name: CI
	on: [push, pull_request]
	jobs:
	test:
	name: Test - ${{ matrix.python-version }}
	runs-on: ubuntu-latest
	strategy:
	matrix:
	python-version:
	- "pypy-3.9"
	- "pypy-3.10"
	- "3.9"
	- "3.10"
	- "3.11"
	- "3.12"
	steps:
	- name: Check out repository
	uses: actions/checkout@v4
	- name: Install Python
	uses: actions/setup-python@v5
	with:
	python-version: ${{ matrix.python-version }}
	check-latest: true
	- name: Install dependencies
	run: python -m pip install tox
	- name: Run tests
	run: \|
	python -m tox -e py
	python -m tox -e noextra
	lint:
	name: Lint
	runs-on: ubuntu-latest
	steps:
	- name: Check out repository
	uses: actions/checkout@v4
	- name: Install Python
	uses: actions/setup-python@v5
	with:
	python-version: "3.x"
	check-latest: true
	- name: Install dependencies
	run: python -m pip install tox
	- name: Run linting
	run: python -m tox -e pep8
	- name: Run mypy
	run: python -m tox -e mypy
	packaging:
	name: Packaging
	runs-on: ubuntu-latest
	steps:
	- name: Check out repository
	uses: actions/checkout@v4
	- name: Install Python
	uses: actions/setup-python@v5
	with:
	python-version: "3.x"
	check-latest: true
	- name: Install dependencies
	run: python -m pip install tox
	- name: Test packaging
	run: python -m tox -e packaging

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