return map.size();
  }

  @Override
  public UnmodifiableIterator<K> iterator() {
    return map.keyIterator();
  }

  @Override
  public Spliterator<K> spliterator() {
    return map.keySpliterator();
  }

  @Override
  public boolean contains(@Nullable Object object) {
    return map.containsKey(object);
  }

  @Override
  K get(int index) {

        return entryIterator.hasNext();
      }

      @Override
      public K next() {
        return entryIterator.next().getKey();
      }
    };
  }

  Spliterator<K> keySpliterator() {
    return CollectSpliterators.map(entrySet().spliterator(), Entry::getKey);
  }

  private transient @Nullable ImmutableCollection<V> cachedValues = null;

  @Override

        return entryIterator.hasNext();
      }

      @Override
      public K next() {
        return entryIterator.next().getKey();
      }
    };
  }

  Spliterator<K> keySpliterator() {
    return CollectSpliterators.map(entrySet().spliterator(), Entry::getKey);
  }

  @LazyInit @RetainedWith private transient @Nullable ImmutableCollection<V> values;

  /**