Update app.py

app.py

@@ -74,7 +74,7 @@ interaction_count = 0
 def interact(user_input, history):
     global tokenizer, model, interaction_count
     try:
-        if tokenizer is None or model is not None:
+        if tokenizer is None or model is None:
             raise ValueError("Tokenizer or model is not initialized.")
         
         # Increment interaction count