code: def variantAnnotationsGenerator(self, request):
          
          compoundId = datamodel.VariantAnnotationSetCompoundId.parse(
              request.variant_annotation_set_id)
          dataset = self.getDataRepository().getDataset(compoundId.dataset_id)
          variantSet = dataset.getVariantSet(compoundId.variant_set_id)
          variantAnnotationSet = variantSet.getVariantAnnotationSet(
              request.variant_annotation_set_id)
          iterator = paging.VariantAnnotationsIntervalIterator(
              request, variantAnnotationSet)
          return iterator
docs: Returns a generator over the (variantAnnotaitons, nextPageToken) pairs
          defined by the specified request.