add app file

app.py

@@ -1,7 +1,8 @@
 import gradio as gr
+import numpy as np
 
 def greet(name):
-    return "Hello " + name + "!!"
+    return (16000, np.random.randn(16000))
 
-iface = gr.Interface(fn=greet, inputs="text", outputs="text")
+iface = gr.Interface(fn=greet, inputs="text", outputs="audio")
 iface.launch()