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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_queryset(self):
 """ Filter the `QuerySet` based on its parents as defined in the `serializer_class.parent_lookup_kwargs`. """

        queryset = super(NestedViewSetMixin, self).get_queryset()
        if hasattr(self.serializer_class, 'parent_lookup_kwargs'):
            orm_filters = {}
            for query_param, field_name in self.serializer_class.parent_lookup_kwargs.items():
                orm_filters[field_name] = self.kwargs[query_param]
            return queryset.filter(**orm_filters)
        return queryset