Add a scheduled GitHub Action to check upstream version #333

	name: CI
	on: [push, pull_request]
	permissions:
	contents: read

	jobs:
	build:

	runs-on: ubuntu-20.04
	strategy:
	matrix:
	python-version: [3.5, 3.6, 3.7, 3.8, 3.9, "3.10", 3.11, pypy2.7, pypy3.9]

	steps:
	- uses: actions/checkout@ac593985615ec2ede58e132d2e21d2b1cbd6127c # v3
	- name: Set up Python ${{ matrix.python-version }}
	uses: actions/setup-python@d27e3f3d7c64b4bbf8e4abfb9b63b83e846e0435 # v4
	with:
	python-version: ${{ matrix.python-version }}
	- name: Install dependencies
	run: \|
	python -m pip install --upgrade pip
	pip install protobuf==3.17.3 pycodestyle
	- name: Lint
	run: make -C tools/python lint
	- name: Test
	run: \|
	make -C tools/python metaclean
	make -C tools/python test
	# Check re-generation didn't change anything (except locale.py)
	git checkout -- python/phonenumbers/geodata/locale.py
	status=$(git status --porcelain ) \|\| :
	if [[ -n ${status} ]]; then
	echo "Regenerated files differ from checked-in versions: ${status}"
	git status
	exit 1
	fi

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