bump setup.py to v0.21.0 #233

	name: Python unit tests

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

	jobs:
	lint:
	runs-on: ubuntu-latest

	steps:
	- uses: actions/checkout@v1
	- name: Set up Python 3.12
	uses: actions/setup-python@v2
	with:
	python-version: 3.12
	- name: Lint with flake8
	run: \|
	python -m pip install --upgrade pip
	pip install flake8
	# 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

	mypy:
	runs-on: ubuntu-latest

	steps:
	- uses: actions/checkout@v1
	- name: Set up Python 3.12
	uses: actions/setup-python@v2
	with:
	python-version: 3.12
	- name: Type checking with mypy
	run: \|
	python -m pip install --upgrade pip
	pip install mypy
	mypy starlette_exporter

	test:
	strategy:
	fail-fast: false
	matrix:
	python-version: ["3.8", "3.9", "3.10", "3.11", "3.12"]

	runs-on: ubuntu-latest

	steps:
	- uses: actions/checkout@v1
	- 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
	pip install -r requirements.txt
	- name: Test with pytest
	run: \|
	pip install pytest
	PYTHONPATH=. pytest

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