return delegate;
    }
    return new UnmodifiableSetMultimap<>(delegate);
  }

  /**
   * Simply returns its argument.
   *
   * @deprecated no need to use this
   * @since 10.0
   */
  @Deprecated
  public static <K, V> SetMultimap<K, V> unmodifiableSetMultimap(
      ImmutableSetMultimap<K, V> delegate) {