drupal-erable/web/modules/custom/erable_mod/erable_mod.module

<?php

/**
 * @file
 * Primary module hooks for reha module.
 */

/**
 * Implements hook_theme().
 */
function erable_mod_theme() {
  return array(
    'svg_mapsites' => array(
      'variables' => array('sites' => [], 'intro' => null),
    ),
  );
}