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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 reprioritize(self, stream_id, depends_on=None, weight=16, exclusive=False):
 """ Update the priority status of an existing stream. :param stream_id: The stream ID of the stream being updated. :param depends_on: (optional) The ID of the stream that the stream now depends on. If ``None``, will be moved to depend on stream 0. :param weight: (optional) The new weight to give the stream. Defaults to 16. :param exclusive: (optional) Whether this stream should now be an exclusive dependency of the new parent. """

        self._priority.reprioritize(stream_id, depends_on, weight, exclusive)