def setSubtitleStream(self, subtitleStreamID, mtype=DEFAULT_MTYPE):
self.setStreams(subtitleStreamID=subtitleStreamID, mtype=mtype)<EOL>
Select the subtitle stream for the current playback item (only video).

            Parameters:
                subtitleStreamID (str): ID of the subtitle stream from the media object.
                mtype (str): Media type to take action against (music, photo, video).