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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_data_fetch(self):
 """Starts a thread that fetches data from the Streams view server. Each item in the returned `Queue` represents a single tuple on the stream the view is attached to. Returns: queue.Queue: Queue containing view data. .. note:: This is a queue of the tuples coverted to Python objects, it is not a queue of :py:class:`ViewItem` objects. """

        self.stop_data_fetch()
        self._data_fetcher = _ViewDataFetcher(self, self._tuple_fn)
        t = threading.Thread(target=self._data_fetcher)
        t.start()
        return self._data_fetcher.items