uswds-8.x-2.1-rc1/preprocess/menu/menu__secondary_menu.preprocess.inc

<?php

/**
 * @file
 * Preprocess function for this hook.
 */

/**
 * Implements hook_preprocess_menu__REGION().
 *
 * This made possible by our custom theme suggestion.
 *
 * @see uswds_theme_suggestions_menu_alter()
 */
function uswds_preprocess_menu__secondary_menu(&$variables) {

}