code: private PubsubFuture<Subscription> createSubscription(final String canonicalSubscriptionName,
                                                          final Subscription subscription) {
      validateCanonicalSubscription(canonicalSubscriptionName);
      return put("create subscription", canonicalSubscriptionName, SubscriptionCreateRequest.of(subscription),
          readJson(Subscription.class));
    }
docs: Create a Pub/Sub subscription.
  
  @param canonicalSubscriptionName The canonical (including project) name of the subscription to create.
  @param subscription              The subscription to create.
  @return A future that is completed when this request is completed.