}
    Set<List<Optional<?>>> cartesianProduct = Sets.cartesianProduct(optionalSets);
    return Iterables.transform(
        cartesianProduct,
        new Function<List<Optional<?>>, List<Object>>() {
          @Override
          public List<Object> apply(List<Optional<?>> objs) {
            return Lists.transform(objs, OPTIONAL_TO_NULLABLE);
          }
        });
  }

    }
    Set<List<Optional<?>>> cartesianProduct = Sets.cartesianProduct(optionalSets);
    return Iterables.transform(
        cartesianProduct,
        new Function<List<Optional<?>>, List<Object>>() {
          @Override
          public List<Object> apply(List<Optional<?>> objs) {
            return Lists.transform(objs, OPTIONAL_TO_NULLABLE);
          }
        });
  }