gpu zero is tricky

app.py

@@ -34,6 +34,9 @@ def start():
 
 def send_message(message, history):
     global tokenizer, model
+    if tokenizer is None or model is None:
+        start()  # Ensure the model and tokenizer are initialized
+
     # Add the user's message to the history
     history.append(("User", message))