python-2.7 - [zguide]pyzmq パブリッシュが機能しない

Question

github から zguide ソースをダウンロードします。Python の例 code-wuserver.py が機能しないことがわかりました。wuserver.py と wuclient.py を実行すると、wuclient.py はデータを受信できませんが、c コードを実行すると wuserver.c,wuclient.py はデータを受信できます。

wuserver.py

#
#   Weather update server
#   Binds PUB socket to tcp://*:5556
#   Publishes random weather updates
#

import zmq
from random import randrange


context = zmq.Context()
socket = context.socket(zmq.PUB)
socket.bind("tcp://*:5556")

while True:
    zipcode = randrange(1, 100000)
    temperature = randrange(-80, 135)
    relhumidity = randrange(10, 60)

    socket.send_string("%i %i %i" % (zipcode, temperature, relhumidity))

wuclient.py

#
#   Weather update client
#   Connects SUB socket to tcp://localhost:5556
#   Collects weather updates and finds avg temp in zipcode
#

import sys
import zmq


#  Socket to talk to server
context = zmq.Context()
socket = context.socket(zmq.SUB)

print("Collecting updates from weather server...")
socket.connect("tcp://localhost:5556")

# Subscribe to zipcode, default is NYC, 10001
zip_filter = sys.argv[1] if len(sys.argv) > 1 else "10001"

# Python 2 - ascii bytes to unicode str
if isinstance(zip_filter, bytes):
    zip_filter = zip_filter.decode('ascii')
socket.setsockopt_string(zmq.SUBSCRIBE, zip_filter)

# Process 5 updates
total_temp = 0
for update_nbr in range(5):
    string = socket.recv_string()
    zipcode, temperature, relhumidity = string.split()
    total_temp += int(temperature)

print("Average temperature for zipcode '%s' was %dF" % (
      zip_filter, total_temp / update_nbr)
)