code: static String accessPseudoLabel(IPseudoAtom atom, String defaultLabel) {
          String label = atom.getLabel();
          if (label != null && !label.isEmpty()) return label;
          return defaultLabel;
      }
docs: Safely access the label of a pseudo atom. If the label is null or empty, the default label is
  returned.
  
  @param atom the pseudo
  @return pseudo label