def _get_app_attr(app: Any, name: str, default: Any = None) -> Any:
 """Retrieves an attribute from the App or its Controller."""
 if hasattr(app, name):
  val = getattr(app, name)
  return val
 if hasattr(app, 'controller') and hasattr(app.controller, name):
  val = getattr(app.controller, name)
  return val
 return default

def _has_app_attr(app: Any, name: str) -> bool:
 """Checks if an attribute exists on the App or its Controller."""
 if hasattr(app, name): return True
 if hasattr(app, 'controller') and hasattr(app.controller, name): return True
 return False

def _set_app_attr(app: Any, name: str, value: Any) -> None:
 """Sets an attribute on the App or its Controller."""
 if hasattr(app, name):
  setattr(app, name, value)
 elif hasattr(app, 'controller'):
  setattr(app.controller, name, value)
 else:
  setattr(app, name, value)