[3.14] Fix example according to PEP 750 in "What's new in 3.14" (GH-134727) (GH-135870)

Fix example according to PEP 750 in "What's new in 3.14" (GH-134727)

A redundant extra part was written. Added a closing tag, to match the usage in PEP 750.
(cherry picked from commit 2793b68f758c10fb63b264787f10d46a71fc8086)

Co-authored-by: Vincent Poulailleau <vpoulailleau@gmail.com>