drop python v3.5 and v3.6 #165

	# This workflow will install Python dependencies, run tests and lint with a variety of Python versions
	# For more information see: https://help.github.com/actions/language-and-framework-guides/using-python-with-github-actions

	name: Gradient-Free-Optimizers

	on:
	push:
	branches:
	- master
	- dev
	pull_request:
	branches:
	- master
	- dev

	jobs:
	build:
	runs-on: ubuntu-20.04
	strategy:
	fail-fast: false
	matrix:
	python-version: ["3.7", "3.8", "3.9", "3.10", "3.11"]

	steps:
	- uses: actions/checkout@master

	- 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 --upgrade pip
	python -m pip install surfaces flake8 pytest
	python -m pip install .
	python -m pip install --upgrade pandas # surfaces install pandas < 2

	- 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: \|
	python -m pytest tests -p no:warnings

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