Iterate over schema dict only once

test/integration/test_config_defaults.py

@@ -259,8 +259,9 @@ def get_config_data():
 
     create_driver()  # create + setup DRIVER
     parent_dirs = load_parent_dirs()  # called after DRIVER is setup
-    items = ((k, v) for k, v in DRIVER.app.config.schema.app_schema.items() if k not in DO_NOT_TEST)
-    for key, data in items:
+    for key, data in DRIVER.app.config.schema.app_schema.items():
+        if key in DO_NOT_TEST:
+            continue
         expected_value = get_expected(key, data, parent_dirs)
         loaded_value = getattr(DRIVER.app.config, key)
         data = OptionData(key=key, expected=expected_value, loaded=loaded_value)  # passed to test