threads.py

class Worker(threading.Thread):
    """Thread executing tasks from a given tasks queue"""
    def __init__(self, tasks):
        threading.Thread.__init__(self)
        self.tasks = tasks
        self.daemon = True
        self.start()

    def run(self):
        while True:
            try:
                func, args, kargs = self.tasks.get()
                func(*args, **kargs)
                self.tasks.task_done()
            except KeyboardInterrupt as ex:
                print "\nInterrupted"
                sys.exit(0)
            except Exception as ex:
                print(traceback.format_exc())

class ThreadPool:
    """Pool of threads consuming tasks from a queue"""
    def __init__(self, num_threads):
        self.tasks = Queue.Queue(num_threads)
        for _ in range(num_threads): Worker(self.tasks)

    def add_task(self, func, *args, **kargs):
        """Add a task to the queue"""
        self.tasks.put((func, args, kargs))

    def wait_completion(self):
        """Wait for completion of all the tasks in the queue"""
        self.tasks.join()