Point is, I'd see this problem constantly until I figured it out. And not once did it take more than a few minutes to fix it because, as you point out, it shows you where the problem is. And if you use PyCharm, or VS Code with Python extension, or a raft of any other editors, it'll bark at you long before you try and run the code, with circles and arrows, and a paragraph on the back of each one explaining the problem.

So, yeah, the author is making shit up. And needs to learn about what the Tab key does.