Separate out Python 2.7 to use custom image #660

	name: Build

	on:
	push:
	branches-ignore:
	- 'release/*'
	pull_request:
	branches:
	- master

	jobs:
	build:
	runs-on: ubuntu-20.04
	env:
	# We use these variables to convert between tox and GHA version literals
	py35: 3.5
	py36: 3.6
	py37: 3.7
	py38: 3.8
	py39: 3.9
	strategy:
	# ensures the entire test matrix is run, even if one permutation fails
	fail-fast: false
	matrix:
	python-version: [py35, py36, py37, py38, py39]
	steps:
	- name: Checkout code
	uses: actions/checkout@v2
	- name: Set up Python ${{ env[matrix.python-version] }}
	uses: actions/setup-python@v2
	with:
	python-version: ${{ env[matrix.python-version] }}
	- name: Install tox
	# Pin tox 3 because of https://github.com/rpkilby/tox-factor/issues/18
	run: pip install -U tox==3.27.1 tox-factor
	- name: Cache tox environment
	uses: actions/cache@v2
	with:
	path: .tox
	# bump version prefix to fully reset caches
	key: v1-tox-${{ matrix.python-version }}-${{ hashFiles('tox.ini', '**/setup.py') }}
	- name: run tox
	run: tox -f ${{ matrix.python-version }}
	build-27:
	runs-on: ubuntu-20.04
	container:
	image: python:2.7.18-buster
	env:
	py27: 2.7
	steps:
	- name: Checkout code
	uses: actions/checkout@v2
	- name: Install tox
	run: pip install -U tox==3.27.1 tox-factor
	- name: Cache tox environment
	uses: actions/cache@v2
	with:
	path: .tox
	key: v1-tox-27-${{ hashFiles('tox.ini', '**/setup.py') }}
	- name: Run tox for Python 2.7
	run: tox -f py27

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