code: @Override
      public boolean isSet(String propName) {
          if (propName.equals(PROP_C)) {
              return isSetC();
          }
          if (propName.equals(PROP_COUNTRY_NAME)) {
              return isSetCountryName();
          }
          if (propName.equals(PROP_DESCRIPTION)) {
              return isSetDescription();
          }
          return super.isSet(propName);
      }
docs: Returns true if the requested property is set; false, otherwise.
  
  @return
  returned object is {@link boolean }