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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def join(self):
 """Wait for this worker to complete its work in progress. This method is useful when testing code. """

        while True:
            for consumer in self.consumers.values():
                consumer.delay_queue.join()

            self.work_queue.join()

            # If nothing got put on the delay queues while we were
            # joining on the work queue then it shoud be safe to exit.
            # This could still miss stuff but the chances are slim.
            for consumer in self.consumers.values():
                if consumer.delay_queue.unfinished_tasks:
                    break
            else:
                if self.work_queue.unfinished_tasks:
                    continue
                return