docs: def _fetch_messages(self):
          """
          Get an input message from the socket
          """
          try:
              [_, msg] = self.socket.recv_multipart(flags=zmq.NOBLOCK)
              if Global.CONFIG_MANAGER.tracing_mode:
                  Global.LOGGER.debug("fetched a new message")
  
              self.fetched = self.fetched + 1
              obj = pickle.loads(msg)
              self._deliver_message(obj)
              return obj
          except zmq.error.Again:
              return None
          except Exception as new_exception:
              Global.LOGGER.error(new_exception)
              raise new_exception