K extends @Nullable Object, V1 extends @Nullable Object, V2 extends @Nullable Object>
      Multimap<K, V2> transformEntries(
          Multimap<K, V1> fromMap, EntryTransformer<? super K, ? super V1, V2> transformer) {
    return new TransformedEntriesMultimap<>(fromMap, transformer);
  }

  /**
   * Returns a view of a {@code ListMultimap} whose values are derived from the original multimap's

              }
            },
            Functions.forMap(INT_TO_STRING_MAP.inverse()));
    assertEquals(INT_TO_STRING_MAP, outputMap);
  }

  public void testUniqueIndexIterator() {
    ImmutableMap<Integer, String> outputMap =
        Maps.uniqueIndex(
            INT_TO_STRING_MAP.values().iterator(), Functions.forMap(INT_TO_STRING_MAP.inverse()));
    assertEquals(INT_TO_STRING_MAP, outputMap);