Interruptible Python multiprocessing pool.

ProcessPool.py

import sys
import multiprocessing
import os
import time

class Pool():
    def __init__(self):
        self.cpu_count = os.cpu_count()
        self.pool = []
        self.pool_lock = multiprocessing.Lock()

    def map(self, target, iterable):
        try:
            while iterable:
                while iterable and len(self.pool) < os.cpu_count():
                    with self.pool_lock:
                        try:
                            p = multiprocessing.Process(target=target, args=(iterable.pop(),), daemon=True)
                            p.start()
                            self.pool.append(p)
                        except IndexError:
                            break
                self.join()
        except KeyboardInterrupt:
            self.join()

    def join(self):
        with self.pool_lock:    
            for p in self.pool:
                p.join()
            self.pool = []

#Example processing function
def run(num):
    try:
        print(num)
        time.sleep(1)
    except KeyboardInterrupt:
        raise

def fetch(num):
    try:
        run(num)
    except:
        sys.exit()


if __name__ == '__main__':
  nums = [i for i in range(100)]
  pool = Pool()
  pool.map(fetch, nums)
  print('done')