Merge commit '9cc63ca' into molmd_fix_3-9 #46

	name: Linting

	on: [push, pull_request]

	jobs:
	build:
	# prevent this action from running on forks
	if: github.repository == 'materialsproject/pymatgen'
	runs-on: ubuntu-latest
	strategy:
	max-parallel: 1
	matrix:
	python-version: [3.9]
	steps:
	- uses: actions/checkout@v2
	with:
	fetch-depth: 0
	- name: Set up Python ${{ matrix.python-version }}
	uses: actions/setup-python@v2
	with:
	python-version: ${{ matrix.python-version }}
	- uses: actions/cache@v2
	with:
	path: ~/.cache/pip
	key: ${{ runner.os }}-pip-${{ hashFiles('requirements-dev.txt') }}
	restore-keys: \|
	${{ runner.os }}-pip-
	- name: Install dependencies
	run: \|
	python -m pip install --upgrade pip
	pip install -r requirements-dev.txt --quiet
	- name: mypy
	run: \|
	mypy --version
	rm -rf .mypy_cache
	mypy pymatgen
	- name: pydocstyle
	run: \|
	pydocstyle --count pymatgen
	- name: pylint
	run: \|
	pylint pymatgen
	- name: black
	run: \|
	black --version
	black --check --diff --color pymatgen
	- name: flake8
	run: \|
	flake8 --version
	flake8 --count --show-source --statistics pymatgen
	# exit-zero treats all errors as warnings.
	flake8 --count --exit-zero --max-complexity=20 --statistics pymatgen

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