Mask entries in simulated SFS out if they are negative and return None #646

	name: lint

	on:
	push:
	pull_request:

	jobs:
	lint:
	runs-on: ubuntu-20.04
	steps:
	- uses: actions/checkout@v2
	- uses: actions/setup-python@v2
	with:
	python-version: 3.6

	- name: Install dependencies
	run: \|
	pip install --upgrade setuptools
	pip install pycodestyle
	pip install flake8
	python setup.py build

	- name: Check code style.
	run: pycodestyle gadma

	- name: flake8
	run: flake8 --exit-zero ./gadma

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