Python poll based multiprocessing example that works

multiprocessing.py

import random

from multiprocessing import Pool,TimeoutError
from time import sleep

servers=["s1","s2","s3","s4","s5","s6","s7","s8","s9","s10","s11","s12","s13","s14","s15","s16","s17","s18","s19","s20","s21","s22","s23","s24","s25","s26","s27","s28","s29","s30"]
blah = "no callback"

def f(x):
    print("start f(" + x + ")")
    sleep(random.randint(10, 20))
    print("end   f(" + x + ")")
    return "did " + x

if __name__ == '__main__':
    pool = Pool(processes=6)
    results = pool.imap(f, servers, chunksize=1)
    while True:
        try:
            print results.next()
        except:
            break