Overwrite pager names in Drupal

pager.inc

/**
 * Implements hook_preprocess_pager().
 */

function THEME_preprocess_pager(&$vars, $hook) {
  $vars['tags'][0] = 'first';
  $vars['tags'][1] = 'previous';
  $vars['tags'][3] = 'next';
  $vars['tags'][4] = 'last';
}