code: def stop(self, exc=None, exit_code=None):
          '''Gracefully stop the :class:`Actor`.
  
          Implemented by the :meth:`.Concurrency.stop` method of the
          :attr:`concurrency` attribute.
          '''
          return self._concurrency.stop(self, exc, exit_codef stop(self, exc=None, exit_code=None):
          '''Gracefully stop the :class:`Actor`.
  
          Implemented by the :meth:`.Concurrency.stop` method of the
          :attr:`concurrency` attribute.
          '''
          return self._concurrency.stop(self, exc, exit_code)
docs: Gracefully stop the :class:`Actor`.
  
          Implemented by the :meth:`.Concurrency.stop` method of the
          :attr:`concurrency` attribute.