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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 save(self, *args, **kwargs):
 """Adds a subscription for the given user to the given object."""

        method_kwargs = self._get_method_kwargs()
        try:
            subscription = Subscription.objects.get(**method_kwargs)
        except Subscription.DoesNotExist:
            subscription = Subscription.objects.create(**method_kwargs)
        return subscription