The Putting your model into production section of Lesson 2 notes describes Simon Willison's [cougar-or-not] (https://github.com/simonw/cougar-or-not) web app deployment using Zeit. It looks like Zeit no longer supports this type of deployment. The article has been removed from the fast.ai course, so the https://course-v3.fast.ai/deployment_zeit.html link is broken and should be removed, and perhaps the description of Zeit for hosting should be updated as well.
@hiromis Many thanks for sharing your excellent notes!