Problems in initial setup

I am trying to host in local server. I have used below link.
https://gist.github.com/ajinasokan/267d68c9f61e3e4ea11681c0ec4e707d

my question is for below points

2. Run python app and ngrok tunnel
- Save the following code to "app.py"
(for this , I have saved the code in app.py in my python library)
- Run the script by "sudo python app.py"
WHERE SHALL I RUN THIS SCRIPT. WHEN I RUN IN ANNACONDA PROMPT, ITS GIVING ERROR