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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_facet_serializer_class(self):
 """ Return the class to use for serializing facets. Defaults to using ``self.facet_serializer_class``. """

        if self.facet_serializer_class is None:
            raise AttributeError(
                "%(cls)s should either include a `facet_serializer_class` attribute, "
                "or override %(cls)s.get_facet_serializer_class() method." %
                {"cls": self.__class__.__name__}
            )
        return self.facet_serializer_class