docs: @NotNull public static Completable from(@NotNull final ApolloPrefetch prefetch) {
      checkNotNull(prefetch, "prefetch == null");
  
      return Completable.create(new CompletableOnSubscribe() {
        @Override public void subscribe(final CompletableEmitter emitter) {
          cancelOnCompletableDisposed(emitter, prefetch);
          prefetch.enqueue(new ApolloPrefetch.Callback() {
            @Override public void onSuccess() {
              if (!emitter.isDisposed()) {
                emitter.onComplete();
              }
            }
  
            @Override public void onFailure(@NotNull ApolloException e) {
              Exceptions.throwIfFatal(e);
              if (!emitter.isDisposed()) {
                emitter.onError(e);
              }
            }
          });
        }
      });
    }