change back to original matplotlib backend #117

	name: Python package

	on: [push, pull_request, workflow_dispatch]

	jobs:
	build:

	runs-on: ${{ matrix.os }}
	strategy:
	matrix:
	python-version: ["3.7", "3.8", "3.9"]
	os: [ubuntu-latest]

	steps:
	- uses: actions/checkout@v3
	- name: Set up Python ${{ matrix.python-version }} on ${{ matrix.os }}
	uses: actions/setup-python@v4
	with:
	python-version: ${{ matrix.python-version }}
	- name: Install dependencies
	run: \|
	python -m pip install --upgrade pip
	pip install flake8 nose pep8 pyyaml
	if [ -f requirements.txt ]; then pip install -r requirements.txt; fi
	- name: Lint with flake8
	run: \|
	# stop the build if there are Python syntax errors or undefined names
	flake8 . --count --select=E9,F63,F7,F82 --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
	run: \|
	python setup.py install
	- name: Test with nosetests
	run: \|
	export PYTHONHASHSEED=0
	nosetests -v tests/test_umi_tools.py

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