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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 get_last_update_of_model(self, model, **kwargs):
 """ Return the last time a given model's items were updated. Returns the epoch if the items were never updated. """

        qs = self.get_for_model(model)
        if kwargs:
            qs = qs.filter(**kwargs)
        try:
            return qs.order_by('-timestamp')[0].timestamp
        except IndexError:
            return datetime.datetime.fromtimestamp(0)