code cleanup + bug fixes #49

	name: PyshGP Tests

	on: [push]

	jobs:
	build:

	runs-on: ubuntu-latest
	strategy:
	max-parallel: 3
	matrix:
	python-version: [3.7, 3.8]

	steps:
	- uses: actions/checkout@v1
	- name: Set up Python ${{ matrix.python-version }}
	uses: actions/setup-python@v1
	with:
	python-version: ${{ matrix.python-version }}
	- name: Install dependencies
	run: \|
	python -m pip install --upgrade pip
	python -m pip install -r requirements.txt
	- name: Lint with flake8
	run: \|
	pip install flake8
	flake8 pyshgp/ --count --select=E9,F63,F7,F82 --show-source --statistics
	flake8 pyshgp/ --count --exit-zero --ignore=E501,D105,D107,E731 --max-complexity=10 --max-line-length=127 --statistics
	flake8 examples/ --count --select=E9,F63,F7,F82 --show-source --statistics
	flake8 examples/ --count --exit-zero --ignore=E501,D105,D107,E731 --max-complexity=10 --max-line-length=127 --statistics
	- name: Test with pytest
	run: \|
	pip install pytest
	pytest
	- name: Test Examples
	run: \|
	pip install . -U
	python examples/string_demo.py
	python examples/string_demo_annealing.py

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