queue_and_workers_read_file_example.py

import multiprocessing
import queue
import time

def worker(input, output):
    for line in iter(input.get, None):
            output.put(len(line))

if __name__ == '__main__':
    num_processes = 3
    with open('text_big.txt') as f:
        task_queue = multiprocessing.Queue(maxsize=10000)
        done_queue = multiprocessing.Queue()

        pool = multiprocessing.Pool(num_processes, worker,(task_queue,done_queue))

        for i, line in enumerate(f):
            task_queue.put(line.strip())
    for _ in range(num_processes):
        task_queue.put(None)
    pool.close()
    pool.join()
    total = 0
    while not done_queue.empty():
        l = done_queue.get()
        total += l
    print(total)