log_plays call back plugin

I have a question with the callback plugin log_plays.py. Under requirements I see whitelist.

Whitelist in configuration: Can you elaborate on what I should add there?

In ansible.cfg I uncommented callback_whitelist = timer, mail… Anything else that I should do?Can someone please guide me?

I tried copying this log_plays.py to my controller and tried executing but its not creating any log.

you enabled the timer and mail callbacks, not the log_plays one, just
remove those and set it to log_plays.

Here are the docs in case I was not clear.
https://github.com/ansible/ansible/blob/devel/docs/docsite/rst/plugins/callback.rst