/**
  * Creates or returns an instance of this class.
  *
  * @since 2.3.0
  *
  * @return Theme_Blvd_Options_API A single instance of this class.
  */
 public static function get_instance()
 {
     if (self::$instance == null) {
         self::$instance = new self();
     }
     return self::$instance;
 }