code: public void list(VersionsListConfiguration configuration) throws AppEngineException {
      Preconditions.checkNotNull(configuration);
  
      List<String> arguments = new ArrayList<>();
      arguments.add("app");
      arguments.add("versions");
      arguments.add("list");
      arguments.addAll(GcloudArgs.get("service", configuration.getService()));
      arguments.addAll(GcloudArgs.get("hide-no-traffic", configuration.getHideNoTraffic()));
      arguments.addAll(GcloudArgs.get("project", configuration.getProjectId()));
  
      execute(arguments);
    }
docs: Lists the versions for a service, or every version of every service if no service is specified.
  
  @throws CloudSdkNotFoundException when the Cloud SDK is not installed where expected
  @throws CloudSdkOutOfDateException when the installed Cloud SDK is too old