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)