Update app.py

app.py

@@ -41,8 +41,7 @@ def chat_inf(system_prompt,prompt,history):
     for response in stream:
         output += response.token.text
         if history:
-            history[-1]=[(prompt,output)]
-            hist=history
+            hist=[history[:hist_len],(prompt,output)]
             #hist=[history,(prompt,output)]
         else:
             hist=[(prompt,output)]