To enable the Twilio add-on, you'll first need to create a Twilio account, including a Twilio phone number (this is used as the from number in your notifications). You'll want to note down your Twilio phone number, Account SID, and Auth Token.
To find your Twilio Account SID and Auth Token, look at the top of your dashboard when logged in to your Twilio account as demonstrated below:

The Auth Token will be hidden by default. Click on the eye icon to reveal it.
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