Added some try/except clauses since MIP backends are an optional extra. #46

	name: pytest_and_coveralls
	on: [push, pull_request]

	jobs:
	build:

	runs-on: ubuntu-latest

	steps:
	- uses: actions/checkout@v3
	- name: Set up Python 3.11
	uses: actions/setup-python@v4
	with:
	python-version: 3.11
	- name: Install dependencies
	run: \|
	python -m pip install --upgrade pip
	pip install wheel
	pip install coveralls
	pip install pytest
	pip install pytest-cov
	pip install -r requirements.txt
	pip install matplotlib
	pip install -e .
	- name: Test with coverage
	run: \|
	pytest --cov=symfit
	- name: Upload to Coveralls
	env:
	GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
	run: \|
	pip install --upgrade coveralls
	coveralls --service=github

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