Error: No such command "serve_chat".

I am trying to run the query `chat_web_best_weights_training.bat` and I am getting the displayed in the screenshot. I have tried all the possible solutions available regarding this but then also it is giving the same error.
My chat_ui.html and all the other python files are in the root directory seq2seq-chatbot.
Tensorflow version is 1.15.0 and flask version is 0.12.4
Please look into the problem. Thankyou!!