code: final void modifyAckDeadline(
        ProjectSubscriptionName subscription, List<String> ackIds, int ackDeadlineSeconds) {
  
      ModifyAckDeadlineRequest request =
          ModifyAckDeadlineRequest.newBuilder()
              .setSubscription(subscription == null ? null : subscription.toString())
              .addAllAckIds(ackIds)
              .setAckDeadlineSeconds(ackDeadlineSeconds)
              .build();
      modifyAckDeadline(request);
    }
docs: /* package-private