Add ruff pre-commit, small cleanup of code. #63

	# This workflow will install Python dependencies, run tests and lint with a variety of Python versions
	# For more information see: https://help.github.com/actions/language-and-framework-guides/using-python-with-github-actions

	name: Tests

	on:
	[push, pull_request]

	jobs:
	tests:
	runs-on: ${{ matrix.os }}
	strategy:
	fail-fast: false
	matrix:
	os: [ubuntu-latest, windows-latest, macos-latest]
	python-version: [3.6, 3.7, 3.8, 3.9, "3.10", pypy3]
	optionals: [none, pandas, numba]
	exclude:
	- python-version: pypy3
	optionals: pandas
	- python-version: pypy3
	optionals: numba
	- python-version: "3.10"
	optionals: numba
	- os: macos-latest
	python-version: pypy3
	- os: windows-latest
	python-version: pypy3

	steps:
	- uses: actions/checkout@v2
	- name: Set up Python ${{ matrix.python-version }}
	uses: actions/setup-python@v2
	with:
	python-version: ${{ matrix.python-version }}
	- name: Install dependencies
	run: \|
	python -m pip install --upgrade pip
	python -m pip install flake8 tox
	- name: Lint with flake8
	run: \|
	# stop the build if there are Python syntax errors or undefined names
	flake8 . --count --select=E9,F63,F7,F82 --show-source --statistics
	# exit-zero treats all errors as warnings. The GitHub editor is 127 chars wide
	flake8 . --count --exit-zero --max-complexity=10 --max-line-length=127 --statistics
	- name: Test with tox/pytest
	run: \|
	tox -e py-${{ matrix.optionals }}
	- name: "Upload coverage to Codecov"
	uses: codecov/codecov-action@v1
	with:
	fail_ci_if_error: false

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