Update app.py

app.py

@@ -86,7 +86,7 @@ with gr.Blocks() as demo:
             yield history
 
     msg.submit(user, [msg, chatbot], [msg, chatbot], queue=False).then(bot, [chatbot, chat_engine_var], chatbot)
-    clear.click(lambda: chat_engine_var.reset(), None, chatbot, queue=False)
+    clear.click(lambda x: x.reset(), chat_engine_var, chatbot, queue=False)
     
 if __name__ == "__main__":
     demo.queue()