code: @SafeVarargs
      public static <T> Set<T> setOf(T... ts) {
          return new HashSet<>(Arrays.asList(ts));
      }
docs: Helper method to create a set of object.
  
  @param ts The objects to add to the set.
  @param <T> The type of objects to add to the set.
  @return A set with the given objets.