from multiprocessing.dummy import Pool as ThreadPool
from random import randint
from time import sleep


def increasing_sleeps():
    """Pointless function to show using your own generator"""

    for i in xrange(10):
        yield i


def rand_sleep(max_time):
    """Takes a max sleep time and sleeps anywhere from 0 to max_time seconds"""

    sleep_time = randint(0, max_time)
    sleep(sleep_time)
    return sleep_time


def sleep_lots():
    """Takes the output of increasing_sleeps() and send it to rand_sleep(),
    yielding the result"""

    # multiprocessing.dummy uses threads instead of processes
    # Use two threads
    pool = ThreadPool(2)
    # imap_unordered returns the results when they are ready,
    # regular imap returns them in the order sent
    for sleep_time in pool.imap_unordered(rand_sleep, increasing_sleeps()):
        yield sleep_time


for sleep_time in sleep_lots():
    print 'Slept', sleep_time, 'seconds'