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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, timeout=None):
 """ Waits for all the tasks to be executed :param timeout: Maximum time to wait (in seconds) :return: True if the queue has been emptied, else False """

        if self._queue.empty():
            # Nothing to wait for...
            return True
        elif timeout is None:
            # Use the original join
            self._queue.join()
            return True
        else:
            # Wait for the condition
            with self._queue.all_tasks_done:
                self._queue.all_tasks_done.wait(timeout)
                return not bool(self._queue.unfinished_tasks)