code: @Override
      public EnableSsoResult enableSso(EnableSsoRequest request) {
          request = beforeClientExecution(request);
          return executeEnableSso(request);
      }
docs: <p>
  Enables single sign-on for a directory.
  </p>
  
  @param enableSsoRequest
  Contains the inputs for the <a>EnableSso</a> operation.
  @return Result of the EnableSso operation returned by the service.
  @throws EntityDoesNotExistException
  The specified entity could not be found.
  @throws InsufficientPermissionsException
  The account does not have sufficient permission to perform the operation.
  @throws AuthenticationFailedException
  An authentication error occurred.
  @throws ClientException
  A client exception has occurred.
  @throws ServiceException
  An exception has occurred in AWS Directory Service.
  @sample AWSDirectoryService.EnableSso
  @see <a href="http://docs.aws.amazon.com/goto/WebAPI/ds-2015-04-16/EnableSso" target="_top">AWS API
  Documentation</a>