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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 report_last_seen_message(current):
 """ Push timestamp of latest message of an ACTIVE channel. This view should be called with timestamp of latest message; - When user opens (clicks on) a channel. - Periodically (eg: setInterval for 15secs) while user staying in a channel. .. code-block:: python # request: { 'view':'_zops_last_seen_msg', 'channel_key': key, 'key': key, 'timestamp': datetime, } # response: { 'status': 'OK', 'code': 200, } """

    sbs = Subscriber(current).objects.filter(channel_id=current.input['channel_key'],
                                             user_id=current.user_id)[0]
    sbs.last_seen_msg_time = current.input['timestamp']
    sbs.save()
    current.output = {
        'status': 'OK',
        'code': 200}