for labels in (sparse_labels, dense_labels):
      # Classes 1,3,8 have 0 predictions, classes -1 and 10 are out of range.
      for class_id in (-1, 1, 3, 8, 10):
        self._test_precision_at_k(
            predictions, labels, k=5, expected=NAN, class_id=class_id)