Update versioneer.py to work with python 3.9 #38

	---
	name: Unit tests

	on: [push, pull_request]

	jobs:
	Python36:
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v1
	- name: Setup Python 3.6
	uses: actions/setup-python@v1
	with:
	python-version: 3.6
	- name: Get Docker image
	run: docker pull suoto/hdl_checker_test:latest
	- name: Run tests
	run: ./run_tests.sh -e py36-linux -- -v
	- name: Upload coverage
	run: bash <(curl -s https://codecov.io/bash)
	Python37:
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v1
	- name: Setup Python 3.7
	uses: actions/setup-python@v1
	with:
	python-version: 3.7
	- name: Get Docker image
	run: docker pull suoto/hdl_checker_test:latest
	- name: Run tests
	run: ./run_tests.sh -e py37-linux -- -v
	- name: Upload coverage
	run: bash <(curl -s https://codecov.io/bash)
	Python38:
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v1
	- name: Setup Python 3.8
	uses: actions/setup-python@v1
	with:
	python-version: 3.8
	- name: Get Docker image
	run: docker pull suoto/hdl_checker_test:latest
	- name: Run tests
	run: ./run_tests.sh -e py38-linux -- -v
	- name: Upload coverage
	run: bash <(curl -s https://codecov.io/bash)

	Pypi:
	runs-on: ubuntu-latest
	needs: [Python36, Python37, Python38]
	steps:
	- uses: actions/checkout@v1
	- name: Build dist
	run: python setup.py sdist
	- name: Publish package
	if: github.event_name == 'push' && startsWith(github.ref, 'refs/tags')
	uses: pypa/gh-action-pypi-publish@master
	with:
	user: __token__
	password: ${{ secrets.pypi_password }}

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