Prepare release 4.5.0 #36

	name: Test and lint

	on:
	push:
	pull_request:

	permissions:
	contents: read

	jobs:
	tests:
	name: Run tests

	strategy:
	fail-fast: false
	matrix:
	# We try to test on the earliest available bugfix release of each
	# Python version, because typing sometimes changed between bugfix releases.
	# For available versions, see:
	# https://raw.githubusercontent.com/actions/python-versions/main/versions-manifest.json
	python-version: ["3.7", "3.7.1", "3.8", "3.8.0", "3.9", "3.9.0", "3.10", "3.10.0", "3.11", "3.11.0", "3.12-dev", "pypy3.9"]

	runs-on: ubuntu-20.04

	steps:
	- uses: actions/checkout@v3

	- name: Set up Python
	uses: actions/setup-python@v4
	with:
	python-version: ${{ matrix.python-version }}

	- name: Test typing_extensions
	continue-on-error: ${{ matrix.python-version == '3.12-dev' }}
	run: \|
	# Be wary of running `pip install` here, since it becomes easy for us to
	# accidentally pick up typing_extensions as installed by a dependency
	cd src
	python -m unittest test_typing_extensions.py

	linting:
	name: Lint

	runs-on: ubuntu-latest

	steps:
	- uses: actions/checkout@v3
	- name: Set up Python
	uses: actions/setup-python@v4
	with:
	python-version: "3"
	cache: "pip"
	cache-dependency-path: "test-requirements.txt"

	- name: Install dependencies
	run: \|
	pip install --upgrade pip
	pip install -r test-requirements.txt

	- name: Lint implementation
	run: flake8

	- name: Lint tests
	run: flake8 --config=.flake8-tests src/test_typing_extensions.py

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