Fix Literal types on python 3.9 when typing_extensions is installed #521

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

	jobs:
	unittest:
	runs-on: ${{ matrix.os }}
	strategy:
	fail-fast: false
	matrix:
	os: [ ubuntu-20.04, macOS-12, windows-2019 ]
	python: [3.8, 3.9]
	steps:
	- uses: actions/checkout@v3
	- uses: actions/setup-python@v4
	with:
	python-version: ${{ matrix.python }}
	- run: pip install tox
	- run: tox -e py-all-extras
	unittest-omegaconf:
	runs-on: ubuntu-20.04
	steps:
	- uses: actions/checkout@v3
	- uses: actions/setup-python@v4
	with:
	python-version: 3.8
	- run: pip install tox
	- run: tox -e omegaconf
	doctest:
	runs-on: ubuntu-20.04
	steps:
	- uses: actions/checkout@v3
	- uses: actions/setup-python@v4
	with:
	python-version: 3.8
	- run: pip install -e .[all,doc]
	- name: Run doc tests
	run: sphinx-build -M doctest sphinx sphinx/_build sphinx/index.rst

Provide feedback