docs: public static String getAttributeNameString(InstancesHeader context,
              int attIndex) {
          if ((context == null) || (attIndex >= context.numAttributes())) {
              return "[att " + (attIndex + 1) + "]";
          }
          int instAttIndex = attIndex < context.classIndex() ? attIndex
                  : attIndex + 1;
          return "[att " + (attIndex + 1) + ":"
                  + context.attribute(instAttIndex).name() + "]";
      }