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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_user_trackers(sender, topic, user, request, response, **kwargs):
 """ Receiver to mark a topic being viewed as read. This can result in marking the related forum tracker as read. """

    TrackingHandler = get_class('forum_tracking.handler', 'TrackingHandler')  # noqa
    track_handler = TrackingHandler()
    track_handler.mark_topic_read(topic, user)