Please no. Most editors have a comment/uncomment function which you can use on multiple lines at once. Abusing triple quoted strings for commenting is bad practice. I'd avoid it out of principle, because it's semantically the same as proper strings and looks the same with code highlighting, so it increases cognitive load. But also because they might be interpreted as docstrings mistakenly, either by other programmers, or the documentation tool itself.

A good rule, especially for beginners, is that triple quotes are primarily for docstrings, and the occasional multi line string. (Too many multi line strings, and it's probably a good idea to put them in a separate file)

Edit: There's also other errors with this "anti-book", including basic stuff like operators. For example, the major operator list at the top is missing "or", the Boolean part probably needs a bit more info on truthiness as "not" works on non-Boolean types also, and the membership test operator ("in") works on many other data types, not just lists. And of course, "!=" == "xor".

If you're using vim, press control-V and move your cursor up or down to create a vertical block. And if you're not, ya gotta get yourself some vim ;)