multiprocessing_fun.py

import time
import multiprocessing

POOLSIZE = 4
N = 10
mgr = multiprocessing.Manager()
done = mgr.dict()   # they don't implement sets. Thread-safe counter???

# this MUST be a globally defined funcion
def f(x):
    global done_count
    print x
    time.sleep(1)
    done[x] = 1

def go():
    pool = multiprocessing.Pool(processes=POOLSIZE)
    pool.map(f, range(N))
    while len(done) < N:
        time.sleep(0.1)
    pool.terminate()

if __name__ == '__main__':
    go()