return map.containsValue(value);
    }

    @Override
    public boolean containsEntry(@CheckForNull Object key, @CheckForNull Object value) {
      return map.entrySet().contains(Maps.immutableEntry(key, value));
    }

    @Override
    public Set<V> get(@ParametricNullness final K key) {
      return new Sets.ImprovedAbstractSet<V>() {
        @Override
        public Iterator<V> iterator() {