@CheckReturnValue
    @NonNull
    @BackpressureSupport(BackpressureKind.NONE)
    @SchedulerSupport(SchedulerSupport.NONE)
    public static <T> Flowable<T> unsafeCreate(Publisher<T> onSubscribe) {
        ObjectHelper.requireNonNull(onSubscribe, "onSubscribe is null");
        if (onSubscribe instanceof Flowable) {
            throw new IllegalArgumentException("unsafeCreate(Flowable) should be upgraded");
        }
        return RxJavaPlugins.onAssembly(new FlowableFromPublisher<T>(onSubscribe));
    }