diff --git a/lib/response.js b/lib/response.js
index d0d80ad40..306559451 100644
--- a/lib/response.js
+++ b/lib/response.js
@@ -280,6 +280,7 @@ module.exports = {
    * @param {String} [alt]
    * @api public
    */
+
   back(alt) {
     const url = this.ctx.get('Referrer') || alt || '/';
     this.redirect(url);