lesson05_imap.py

# SuperFastPython.com
# example of executing multiple tasks one-by-one
from time import sleep
from random import random
from multiprocessing import Pool

# custom function to be executed in a child process
def task(arg):
 # block for a random fraction of a second
 sleep(random())
 # report a message
 print(f'From another process {arg}', flush=True)
 # return a value
 return arg * 2

# protect the entry point
if __name__ == '__main__':
 # create the multiprocessing pool
 with Pool(4) as pool:
 # issue multiple tasks and process return values
 for result in pool.imap(task, range(10)):
 print(result)