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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 next_on(context, rrevent=None):
 """ Displays when the next occurence of a recurring event will be. If the recurring event is not specified it is assumed to be the current page. """

    request = context['request']
    if rrevent is None:
        rrevent = context.get('page')
    eventNextOn = getattr(rrevent, '_nextOn', lambda _:None)
    return eventNextOn(request)