import threading
from random import random
from time import sleep

class WorkerPool:

    def __init__(self, workers_number, target, worker_args):
        self._workers_number = workers_number
        self._target = target
        self._worker_args = worker_args
        self._workers = []
        for i in range(self._workers_number):
            # sleep(random())
            worker = threading.Thread(target=self._target, args=worker_args + (i,))
            worker.start()
            self._workers.append(worker)

    def add_stoppers(self, q):
        for i in range(self._workers_number):
            q.put(None)

    def join_workers(self):
        for worker in self._workers:
            worker.join()