[3.10] bpo-45246: Document that sorted() only uses "<" comparisons (GH-28494) (GH-28502)

(cherry picked from commit 9a0dcc5b2e04d9c51350107734f12a1cbc0284a7)

Co-authored-by: Raymond Hettinger <rhettinger@users.noreply.github.com>
1 file changed