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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 start(self):
 """Starts the worker threads"""

        if self.working:
            return
        self.working = True
        for i in range(self.num_workers):
            w = threading.Thread(
                name="Worker Thread #{i}".format(i=i),
                target=self._worker,
                )
            w.daemon = True
            w.start()
            self.workers.append(w)