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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):
 """ This viewset provides a helper attribute to prefetch related models based on the include specified in the URL. __all__ can be used to specify a prefetch which should be done regardless of the include .. code:: python # When MyViewSet is called with ?include=author it will prefetch author and authorbio class MyViewSet(viewsets.ModelViewSet):
 queryset = Book.objects.all() prefetch_for_includes = { '__all__': [], 'author': ['author', 'author__authorbio'], 'category.section': ['category'] } """

        qs = super(PrefetchForIncludesHelperMixin, self).get_queryset()
        if not hasattr(self, 'prefetch_for_includes'):
            return qs

        includes = self.request.GET.get('include', '').split(',')
        for inc in includes + ['__all__']:
            prefetches = self.prefetch_for_includes.get(inc)
            if prefetches:
                qs = qs.prefetch_related(*prefetches)

        return qs