def subscribe(self, topic=b''):
        """subscribe to the SUB socket, to listen for incomming variables, return a stream that can be listened to."""
        self.sockets[zmq.SUB].setsockopt(zmq.SUBSCRIBE, topic)
        poller = self.pollers[zmq.SUB]
        return poller
def subscribe ( self , topic = b'' ) : self . sockets [ zmq . SUB ] . setsockopt ( zmq . SUBSCRIBE , topic ) poller = self . pollers [ zmq . SUB ] return poller
subscribe to the SUB socket, to listen for incomming variables, return a stream that can be listened to.