Lint

Fix bug in df.incore and nr_direct_dot.c #858

	name: Lint

	on: [push, pull_request]

	jobs:
	flake:
	runs-on: ubuntu-20.04
	steps:
	- name: Setup Python
	uses: actions/setup-python@v2
	with:
	python-version: 3.7
	- uses: actions/checkout@v2
	- name: Install flake8
	run: pip install "flake8>=3.7.0"
	- name: Static analysis
	run: flake8 --config .flake8 pyscf

	# - name: Static analysis
	# uses: suo/flake8-github-action@releases/v1
	# with:
	# checkName: 'flake' # NOTE: this needs to be the same as the job name
	# env:
	# GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
	# run: flake8 --config .flake8 pyscf

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