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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 delete(self, *args, **kwargs):
 """ Update the ordering values for siblings. """

        lookup = self.with_respect_to()
        lookup["_order__gte"] = self._order
        concrete_model = base_concrete_model(Orderable, self)
        after = concrete_model.objects.filter(**lookup)
        after.update(_order=models.F("_order") - 1)
        super(Orderable, self).delete(*args, **kwargs)