code: @SuppressWarnings("unchecked")
      private static <T> List<T> cast(List<?> list) {
          return (List<T>)list;
      }
docs: This method will cast {@code Set<?>} to {@code List<T>}
  assuming {@code ?} is castable to {@code T}.
  
  @param <T> the generic type
  @param list a {@code List} object
  @return a casted {@code List} object