docs: def bulk_send(self, topic, kmsgs):
          """ Send a batch of messages
  
          :param str topic: a kafka topic
          :param ksr.transport.Message kmsgs: Messages to serialize
          :return: Execution result
          :rtype: kser.result.Result
          """
  
          try:
              self.client.do_request(
                  method="POST", path="/topic/{}".format(topic), data=[
                      dict(Value=k.MARSHMALLOW_SCHEMA.dump(k)) for k in kmsgs
                  ]
              )
              return Result(stdout="{} message(s) sent".format(len(kmsgs)))
  
          except Exception as exc:
              return Result.from_exception(exc)