In this lesson, you’ll modify your code to listen for and then respond to events. An event is something that happens on Discord that you can use to trigger a reaction in your code.
Continuing to build on the previous code you’ve been working with, the on_ready() event handler handles the event that the Client has made a connection to Discord and prepared its response data. So, when Discord fires an event, discord.py will route the event data to the corresponding event handler on your connected Client.

Jeff on Dec. 21, 2020
If you’re not receiving a DM from your bot, and you are using discord.py v1.5.0 or above, see the docs for Gateway Intents.
You’ll need to add: