try

app.py

@@ -93,7 +93,7 @@ def respond(message,history):
     
 
 
-with gr.Blocks(theme='hmb/amethyst') as chatbot:
+with gr.Blocks(theme='hmb/amethyst') as demo:
     with gr.Row(equal_height=True):
         with gr.Column(scale=10):
             gr.Markdown(
@@ -116,5 +116,5 @@ with gr.Blocks(theme='hmb/amethyst') as chatbot:
     msg.submit(respond, [msg, chatbot], [msg, chatbot])
     send.click(respond, [msg, chatbot], [msg, chatbot])
 
-
+demo.launch()
 chatbot.launch()