[#951] Trying to fix circular import 3, setuptools<64 #306

	name: Ubuntu, py 3.8, pip

	on:
	push:
	branches-ignore:
	- master
	- devel
	- deploy-test
	pull_request:
	branches-ignore:
	- master
	- devel
	- deploy-test
	jobs:
	build-linux:
	runs-on: ubuntu-latest
	strategy:
	max-parallel: 5
	steps:
	- uses: actions/checkout@v2
	- name: Set up Python 3.9
	uses: actions/setup-python@v2
	with:
	python-version: 3.9
	- name: Install dependencies
	run: \|
	pip install --upgrade pip
	pip install flake8 pytest coverage wheel
	pip install -r requirements.txt # fix
	- name: Lint with flake8
	run: \|
	# stop the build if there are Python syntax errors or undefined names
	# too many F82 errors, should uncomment the following line
	flake8 . --count --select=E9,F63,F7 --show-source --statistics
	# exit-zero treats all errors as warnings. The GitHub editor is 127 chars wide
	flake8 . --count --exit-zero --max-complexity=10 --max-line-length=127 --statistics
	- name: install tofu
	run: \|
	pip install -e ".[dev]" --no-build-isolation
	- name: Test with pytest and coverage
	run: \|
	coverage run --source=tofu/ -m pytest tofu/tests -x -v --durations=10

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