Update app.py

app.py

@@ -1 +1,9 @@
-print("Hello World!")
+import gradio as gr
+
+def greet(name):
+    return "Hello " + name + "!"
+
+demo = gr.Interface(fn=greet, inputs="textbox", outputs="textbox")
+    
+if __name__ == "__main__":
+    demo.launch()