Add a method "to_cpu" to convert GPU module to CPU module #1

	name: Lint

	on: [push, pull_request]

	jobs:
	flake:
	runs-on: ubuntu-latest
	steps:
	- name: Checkout
	uses: actions/checkout@v4
	- name: Set up Python
	uses: actions/setup-python@v4
	with:
	python-version: 3.9
	- name: Install flake8
	run: pip install "flake8>=3.7.0"
	- name: Static analysis
	run: flake8 --config .flake8 gpu4pyscf

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