docs: def xgroup_delconsumer(self, name, groupname, consumername):
          """
          Remove a specific consumer from a consumer group.
          Returns the number of pending messages that the consumer had before it
          was deleted.
          name: name of the stream.
          groupname: name of the consumer group.
          consumername: name of consumer to delete
          """
          return self.execute_command('XGROUP DELCONSUMER', name, groupname,
                                      consumername)