Update app.py

app.py

@@ -42,8 +42,8 @@ model = load_model()
 
 def generate_response(message, history):
     try:
-        if model is None:
-            return "Model failed to load. Please check the logs and try again."
+        if model is None or tokenizer is None:
+            return "Model or tokenizer failed to load. Please check the logs and try again."
 
         # Prepare the input
         messages = []