@Nonnull
    @SuppressWarnings("checkstyle:needbraces")
    public static <T> AggregateOperation1<T, PickAnyAccumulator<T>, T> pickAny() {
        return AggregateOperation
                .withCreate(PickAnyAccumulator<T>::new)
                .<T>andAccumulate(PickAnyAccumulator::accumulate)
                .andCombine(PickAnyAccumulator::combine)
                .andExportFinish(PickAnyAccumulator::get);
    }
@Test
    public void when_pickAny_noInput_then_nullResult() {
        // Given
        AggregateOperation1<Object, PickAnyAccumulator<Object>, Object> aggrOp = pickAny();

        // When
        Object result = aggrOp.finishFn().apply(aggrOp.createFn().get());

        // Then
        assertNull(result);
    }