docs: def reset(self):
          """Reset a task.
  
          Allows a task to be started again, clears the ``return_values``.
  
          Raises:
              RuntimeError: If the task has not been stopped.
          """
          if self._status is not TaskStatus.STOPPED:
              raise RuntimeError("Cannot reset %s in state %s" %
                                 (self, self._status))
          self._reset()
          self.return_values = {}
          self._status = TaskStatus.IDLE