fix the to_subgroup bug #704

	name: tests

	on:
	push:
	paths:
	- '**.py' # only run workflow when source files changed
	pull_request:
	paths:
	- '**.py'

	jobs:
	tests:
	runs-on: ubuntu-latest
	strategy:
	matrix:
	python-version: ["3.9", "3.10"]

	steps:
	- uses: actions/checkout@v2
	- name: Set up Python ${{ matrix.python-version }}
	uses: actions/setup-python@v2
	with:
	python-version: ${{ matrix.python-version }}
	- name: Install dependencies
	run: \|
	python -m pip install -U pip
	#pip install nose #pytest # flake8
	pip install --quiet -r requirements.txt
	# - name: Lint with flake8
	# run: \|
	# # stop the build if there are Python syntax errors or undefined names
	# flake8 . --count --select=E9,F63,F7,F82 --show-source --statistics
	# # exit-zero treats all errors as warnings. The GitHub editor is 127 chars wide
	# flake8 . --count --exit-zero --max-complexity=10 --max-line-length=127 --statistics
	- name: Test with pytest
	run: \|
	pip install wheel pytest coverage pytest-cov
	python -m pytest pyxtal/test_all.py
	#nosetests -s

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