How to theming taxonomy page vocabulary name in drupal.

template.php

<?php
function THEMENAME_preprocess_page(&$variables, $hook) {
  
// Theming page--NODETYPE.tpl.php
  if (isset($variables['node'])) {
    $variables['theme_hook_suggestions'][] = 'page__' . $variables['node'] -> type;
  }

  /*Template sugestion for vocabulary NAME (String)*/
  /*Ex: page--vocabulary--VOCABULARYNAME.tpl.php*/

  if (arg(0) == 'taxonomy' && arg(1) == 'term' && is_numeric(arg(2))) {
    $tid = arg(2);

    $query = db_select('taxonomy_vocabulary', 'tv');
    $query -> join('taxonomy_term_data', 'ttd', 'tv.vid = ttd.vid and ttd.tid=:tid', array(':tid' => $tid));
    $query -> fields('tv', array('machine_name'));

    $vname = $query -> execute() -> fetchField();

    $variables['theme_hook_suggestions'][] = 'page__vocabulary_' . $vname;

  }
}