<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def pull(self):
 """ Returns an iterable that can be used to iterate over incoming messages, that were pushed by a push socket. Note that the iterable returns as many parts as sent by pushers. :rtype: generator """

        sock = self.__sock(zmq.PULL)
        return self.__recv_generator(sock)