default branin value

app.py

@@ -18,6 +18,6 @@ iface = gr.Interface(
         gr.Number(0.25, label="x1", minimum=0.0, maximum=1.0),
         gr.Number(0.75, label="x2", minimum=0.0, maximum=1.0),
     ],
-    outputs=gr.Number(label="branin function value"),
+    outputs=gr.Number(branin(0.25, 0.75), label="branin function value"),
 )
 iface.launch()