bpo-47235: Note where a typo is intentional in code. (GH-32348)

bpo-47235: Note where a typo is intentional in code. (GH-32348)

People keep popping up reporting these as typos in the docs despite
being described as typos in the surrounding text.  Hopefully a comment
on the line itself makes it more obvious?

Arguably some of the typo examples are not using the "right" typo as the
"assret" one in particular is now detected by default due to how common
it was in actual code.  But I don't want to to typo chasing by changing
these examples to be other not yet auto-detected typos as they still
illustrate the point well enough.
(cherry picked from commit ac1fb07b6ecb6b93446484f52894914e5199de63)

Co-authored-by: Gregory P. Smith <greg@krypto.org>