Fixed errors with return statement

app.py

@@ -3,13 +3,13 @@ import random
 
 def echo(message, history):
     print("Hello, world!")    
-    return response
+    return message
 
 def yes_or_no(message, history):
     responses = ['yes', 'no']
     print("message:", message)
     print("history:", history)
-    return random.choice(response)
+    return random.choice(responses)
 
 chatbot = gr.ChatInterface(yes_or_no, type='messages')
 chatbot.launch()