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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 update(self, track=values.unset, publisher=values.unset, kind=values.unset, status=values.unset):
 """ Update the SubscribedTrackInstance :param unicode track: The track :param unicode publisher: The publisher :param SubscribedTrackInstance.Kind kind: The kind :param SubscribedTrackInstance.Status status: The status :returns: Updated SubscribedTrackInstance :rtype: twilio.rest.video.v1.room.room_participant.room_participant_subscribed_track.SubscribedTrackInstance """

        data = values.of({'Track': track, 'Publisher': publisher, 'Kind': kind, 'Status': status, })

        payload = self._version.update(
            'POST',
            self._uri,
            data=data,
        )

        return SubscribedTrackInstance(
            self._version,
            payload,
            room_sid=self._solution['room_sid'],
            subscriber_sid=self._solution['subscriber_sid'],
        )