A full example of a producer/consumer using process pools in python

pool.py

from threading import Event
from time import sleep
from traceback import print_exception
from multiprocessing import Pool, Manager
from queue import Full
from signal import signal, SIGTERM, SIGINT

class Consumer1:
  def __init__(self):
    print("Initializing Consumer1 ...")
  
  def consume(self, batch):
    sleep(0.001)

class Consumer2:
  def __init__(self):
    print("Initializing Consumer2 ...")
  
  def consume(self, batch):
    pass

def consume(q):
  consumers = [Consumer1(), Consumer2()]
  
  while True:
    batch = q.get()
    for consumer in consumers:
      consumer.consume(batch)

if __name__ == '__main__':  
  num_processes = 10

  with Pool(num_processes) as pool:
    batch = 0
    stopped = Event()
    queue = Manager().Queue(num_processes)
    
    for n in [SIGINT, SIGTERM]:
      signal(n, lambda *a: stopped.set())

    def error(ex):
      print(ex)
      print_exception(type(ex), ex, ex.__traceback__)
      stopped.set()

    for i in range(num_processes):
      pool.apply_async(consume, (queue,), {}, None, error)

    while not stopped.is_set():
      batch += 1

      try:
        queue.put_nowait(batch)
      except Full:
        print("skipped batch", batch)
    
    print("Terminating pool ...")
    pool.terminate()