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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 changelist_view(self, *args, **kwargs):
 """ Redirect to the add view if no records exist or the change view if the singleton instance exists. """

        try:
            singleton = self.model.objects.get()
        except self.model.MultipleObjectsReturned:
            return super(SingletonAdmin, self).changelist_view(*args, **kwargs)
        except self.model.DoesNotExist:
            return redirect(admin_url(self.model, "add"))
        return redirect(admin_url(self.model, "change", singleton.id))