Update app.py

app.py

@@ -9,7 +9,7 @@ client = InferenceClient("mistralai/Mixtral-8x7B-Instruct-v0.1")
 
 def format_prompt(message, history):
     prompt = "<s>"
-    if not history==[("","")]:
+    if not history==("",""):
         for user_prompt, bot_response in history:
             prompt += f"[INST] {user_prompt} [/INST]"
             prompt += f" {bot_response}</s> "