code: def get_gae_labels(self):
          
          gae_labels = {}
  
          trace_id = get_trace_id()
          if trace_id is not None:
              gae_labels[_TRACE_ID_LABEL] = trace_id
  
          return gae_labels
docs: Return the labels for GAE app.
  
          If the trace ID can be detected, it will be included as a label.
          Currently, no other labels are included.
  
          :rtype: dict
          :returns: Labels for GAE app.