Fix `parametric` covariance for `isinstance` #416

	name: CI

	on:
	- push
	- pull_request

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

	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 --upgrade pip
	python -m pip install --upgrade --no-cache-dir -e '.[dev]'
	- name: Test linter assertions
	run: \|
	python check_linter_assertions.py tests/typechecked
	- name: Test
	env:
	GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
	COVERALLS_FLAG_NAME: ${{ matrix.python-version }}
	COVERALLS_PARALLEL: true
	run: \|
	PRAGMA_VERSION=`python -c "import sys; print('.'.join(map(str, sys.version_info[:2])))"` \
	pytest -v --cov=plum --cov-report term-missing
	coveralls --service=github
	coveralls:
	name: Finish coverage
	needs: test
	runs-on: ubuntu-latest
	container: python:3-slim
	steps:
	- name: Finished
	run: \|
	pip3 install --upgrade coveralls
	coveralls --finish
	env:
	GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}

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