docs: private List<GeneratorTask> createWaiterClassTasks() throws IOException {
          Metadata metadata = model.getMetadata();
          final String className = metadata.getSyncInterface() + "Waiters";
          Map<String, Object> dataModel = ImmutableMapParameter.of(
                  "fileHeader", model.getFileHeader(),
                  "className", className,
                  "waiters", model.getWaiters(),
                  "operation", model.getOperations(),
                  "metadata", metadata);
  
          return Collections.singletonList(new FreemarkerGeneratorTask(waiterClassDir,
                                                                       className,
                                                                       freemarker.getWaiterTemplate(),
                                                                       dataModel));
      }