Please don't backport any of these. Only actual bug fixes should be back ported.

The devguide (https://devguide.python.org/gh-labels/?highlight=backport) says "Generally, backports to the maintenance branches are primarily bugfixes and documentation clarifications." This is a documentation clarification, so it seems fine to backport it.

I am not sure about this. We still keep versionchanged directives for versions >= 3.0 in docs. Even if nobody currently uses Python 3.2, the old (and still working) code can have references to IOError.

That's a good point. IOError isn't mentioned anywhere else in the chunk docs, so I'll revert those changes. (chunk is also now deprecated, so probably not worth worrying about.)

socket.error is documented elsewhere in the module, though, so I think it makes sense to remove the note in the socket docs. Do you agree?