Update app.py

app.py

@@ -15,7 +15,7 @@ def converse(user_input, chat_history=[]):
     user_input_ids = chat_tkn(user_input + chat_tkn.eos_token, return_tensors='pt').input_ids
 
     # create a combined tensor with chat history
-    bot_input_ids = torch.stack([torch.LongTensor(chat_history), user_input_ids], dim=-1)
+    bot_input_ids = torch.cat([torch.LongTensor(chat_history), user_input_ids], dim=-1)
 
     # generate a response 
     chat_history = mdl.generate(bot_input_ids, max_length=1000, pad_token_id=chat_tkn.eos_token_id).tolist()