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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(self, *args, **kwargs):
 """Return the single item from the filtered queryset."""

        assert not args
        assert list(kwargs.keys()) == ['pk']
        pk = kwargs['pk']
        model_name = self.model.__name__
        object_spec = (model_name, pk, None)
        instances = self.cache.get_instances((object_spec,))
        try:
            model_data = instances[(model_name, pk)][0]
        except KeyError:
            raise self.model.DoesNotExist(
                "No match for %r with args %r, kwargs %r" %
                (self.model, args, kwargs))
        else:
            return CachedModel(self.model, model_data)