Update app.py

app.py

@@ -40,13 +40,10 @@ function start() {
     const urlParams = new URLSearchParams(window.location.search);
     var parampdf = urlParams.get('pdfurl')
     var parammod = urlParams.get('mod')
-    var mod
-    if (parammod) {
-       mod=parammod; 
-    } else {
-        mod="en_US-joe-medium";
-    }
-    return parampdf,mod;
+    if (parammod === "") {
+        parammod="en_US-joe-medium";
+    };
+    return parampdf,parammod;
 }"""
 
 with gr.Blocks() as app: