change chap9 code for flake8 #7

	name: python static checks and tests
	on:
	push:
	branches: ["main"]

	jobs:
	testing:
	runs-on: ubuntu-22.04
	steps:
	- uses: actions/checkout@v1
	- name: Setup Python
	uses: actions/setup-python@v1
	with:
	python-version: 3.12.7
	architecture: x64
	- name: Install Flake8
	run: pip install flake8
	- name: Run Flake8
	run: flake8 airflow/chap9
	- name: Install Pylint
	run: pip install pylint
	- name: Run Pylint
	run: find airflow/chap9/ -name "*.py" \| xargs pylint --output-format=colorized
	- name: Install Black
	run: pip install black
	- name: Run Black
	run: find airflow/chap9/ -name "*.py" \| xargs black --check

	- name: Install dependencies
	run: pip install apache-airflow pytest

	- name: Test DAG integrity
	run: pytest airflow/chap9/tests/

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