code: def API_GET(self):  # pylint: disable=arguments-differ
          
          if self.user_manager.session_logged_in():
              return 200, {"authenticated": True, "username": self.user_manager.session_username()}
          else:
              return 200, {"authenticated": False}
docs: Returns {"authenticated": false} or {"authenticated": true, "username": "your_username"} (always 200 OK)