public static <InputT> KeyByBuilder<InputT> of(PCollection<InputT> input) {
    return named(null).of(input);
  }
@Test
  public void testBuild_ImplicitName() {
    final PCollection<String> dataset = TestUtils.createMockDataset(TypeDescriptors.strings());
    final PCollection<KV<String, Long>> reduced =
        ReduceByKey.of(dataset).keyBy(s -> s).valueBy(s -> 1L).combineBy(Sums.ofLongs()).output();
    final ReduceByKey reduce = (ReduceByKey) TestUtils.getProducer(reduced);
    assertFalse(reduce.getName().isPresent());
  }