change chap9 code for flake8

airflow/chap9/dags/bash_command.py

@@ -1,11 +1,11 @@
-from airflow import DAG 
+from airflow import DAG
 from airflow.operators.bash import BashOperator
 import datetime as dt
 with DAG(
     dag_id="bash_command",
-    start_date=dt.datetime(2024, 10,11),
+    start_date=dt.datetime(2024, 10, 11),
     schedule_interval="@once"
 ):
     BashOperator(
         task_id="this_should_fail"
-    )
+    )

airflow/chap9/dags/cycle_dag.py

@@ -11,4 +11,4 @@
     t2 = DummyOperator(task_id="t2")
     t3 = DummyOperator(task_id="t3")
 
-    t1 >> t2 >> t3 >> t1
+    t1 >> t2 >> t3 >> t1

airflow/chap9/tests/dags/test_dag_integrity.py

@@ -1,16 +1,17 @@
 import glob
 import importlib.util
-import os 
+import os
 
 import pytest
-from airflow.models import DAG 
+from airflow.models import DAG
 from airflow.utils.dag_cycle_tester import check_cycle
 
 DAG_PATH = os.path.join(
     os.path.dirname(__file__), "..", "..", "dags/**/*.py"
 )
 DAG_FILES = glob.glob(DAG_PATH, recursive=True)
 
+
 @pytest.mark.parametrize("dag_file", DAG_FILES)
 def test_dag_integrity(dag_file):
     module_name, _ = os.path.splitext(dag_file)
@@ -19,9 +20,10 @@ def test_dag_integrity(dag_file):
     module = importlib.util.module_from_spec(mod_spec)
     mod_spec.loader.exec_module(module)
 
-    dag_objects = [var for var in vars(module).values() if isinstance(var, DAG)]
+    dag_objects = [var for var in vars(module).values() 
+                   if isinstance(var, DAG)]
     assert dag_objects
 
     for dag in dag_objects:
         # Test cycles
-        check_cycle(dag)
+        check_cycle(dag)