STY: fixed flake8 errors in gui.py #4

	name: Unit tests

	on:
	push:
	branches: ['**']
	pull_request:
	branches: ['**']

	jobs:
	build:

	runs-on: ${{ matrix.os }}
	strategy:
	matrix:
	os: [macos-latest]
	python-version: [3.8, 3.9]

	steps:
	- uses: actions/checkout@v4
	- uses: conda-incubator/setup-miniconda@v3
	with:
	activate-environment: test
	python-version: ${{ matrix.python-version }}
	fetch-depth: 2
	- name: Install ubuntu dependencies
	shell: bash -el {0}
	run: \|
	if [ "${{ matrix.os }}" == "ubuntu-latest" ]; then
	sudo add-apt-repository ppa:ubuntu-toolchain-r/test
	sudo apt-get update
	sudo apt-get install libopenmpi-dev openmpi-bin
	fi;
	- name: Install dependencies
	shell: bash -el {0}
	run: \|
	python -m pip install --upgrade pip
	conda install --yes -c conda-forge mpi4py openmpi
	- name: Install HNN-core
	shell: bash -el {0}
	run: \|
	pip install --verbose '.[opt, parallel, test, gui]'
	- name: Lint with flake8
	shell: bash -el {0}
	run: \|
	flake8 --count hnn_core
	- name: Test with pytest
	shell: bash -el {0}
	run: \|
	python -m pytest ./hnn_core/tests/ --cov=hnn_core --cov-report=xml
	- name: Upload coverage to Codecov
	shell: bash -el {0}
	run: \|
	bash <(curl -s https://codecov.io/bash) -f ./coverage.xml

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