Update app.py

app.py

@@ -32,7 +32,7 @@ def format_chat_history(messages: list) -> list:
             
         print(f"t2 {message}")
         formatted_history.append({
-            "role": "user" if message.get("role") == "user" else "assistant",
+            "role": "user" if message.get("role") == "user" else "model",
             "parts": [message.get("content", "")]
         })