Update app.py

app.py

@@ -119,7 +119,7 @@ function custom(){
     Wait(function(){
         return document.querySelector("div#prompt input")
     },function(){
-        document.querySelector("div#prompt input").setAttribute(maxlength,"38");
+        document.querySelector("div#prompt input").setAttribute("maxlength","38");
     },function(){});
 }
 """