/**
  * Method to delete a download permission from the database.
  *
  * @param WC_Customer_Download $download
  * @param array $args Array of args to pass to the delete method.
  */
 public function delete(&$download, $args = array())
 {
     global $wpdb;
     $wpdb->query($wpdb->prepare("\n\t\t\tDELETE FROM {$wpdb->prefix}woocommerce_downloadable_product_permissions\n\t\t\tWHERE permission_id = %d\n\t\t", $download->get_id()));
     $download->set_id(0);
 }