public function generate_order_key() {
		/**
		 * Modify the generated order key for the order.
		 *
		 * @since 3.0.0
		 * @since 5.2.1 Added the `$order` parameter.
		 *
		 * @param string     $order_key The generated order key.
		 * @param LLMS_Order $order_key Order object.
		 */
		return apply_filters( 'lifterlms_generate_order_key', uniqid( 'order-' ), $this );
	}