Lazy Pirate client in Python

#
# Lazy Pirate client
# Use zmq_poll to do a safe request-reply
# To run, start lpserver and then randomly kill/restart it
#
# Author: Daniel Lundin <dln(at)eintr(dot)org>
#
from __future__ import print_function

import zmq

REQUEST_TIMEOUT = 2500
REQUEST_RETRIES = 3
SERVER_ENDPOINT = "tcp://localhost:5555"

context = zmq.Context(1)

print("I: Connecting to server…")
client = context.socket(zmq.REQ)
client.connect(SERVER_ENDPOINT)

poll = zmq.Poller()
poll.register(client, zmq.POLLIN)

sequence = 0
retries_left = REQUEST_RETRIES
while retries_left:
sequence += 1
request = str(sequence).encode()
print("I: Sending (%s)" % request)
client.send(request)

expect_reply = True
while expect_reply:
socks = dict(poll.poll(REQUEST_TIMEOUT))
if socks.get(client) == zmq.POLLIN:
reply = client.recv()
if not reply:
break
if int(reply) == sequence:
print("I: Server replied OK (%s)" % reply)
retries_left = REQUEST_RETRIES
expect_reply = False
else:
print("E: Malformed reply from server: %s" % reply)

else:
print("W: No response from server, retrying…")
# Socket is confused. Close and remove it.
client.setsockopt(zmq.LINGER, 0)
client.close()
poll.unregister(client)
retries_left -= 1
if retries_left == 0:
print("E: Server seems to be offline, abandoning")
break
print("I: Reconnecting and resending (%s)" % request)
# Create new connection
client = context.socket(zmq.REQ)
client.connect(SERVER_ENDPOINT)
poll.register(client, zmq.POLLIN)
client.send(request)

context.term()