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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 event dispatcher. Initiates executor and start polling events. Raises: IllegalStateError: Can't start a dispatcher again when it's already running. """

        if not self.started:
            self.started = True
            self.executor = ThreadPoolExecutor(max_workers=32)
            self.poller = self.executor.submit(self.poll_events)
        else:
            raise IllegalStateError("Dispatcher is already started.")