code: def send_message(self, message):
          
          if not isinstance(message, txdbus.DbusMessage):
              raise TypeError('message: expecting DbusMessage instance (got {!r})',
                                  type(message).__name__)
          self._name_acquired.wait()
          if self._error:
              raise compat.saved_exc(self._error)
          elif self._transport is None:
              raise DbusError('not connected')
          self._writer.write(message.rawMessage)
docs: Send a D-BUS message.
  
          The *message* argument must be ``gruvi.txdbus.DbusMessage`` instance.