bpo-40013: Clarify documentation of restval in csv.DictReader (GH-19099) (GH-19141)

(cherry picked from commit 4b3252cb764807fdb3a661b458d43e4af55cf4df)


Co-authored-by: Juhana Jauhiainen <juhana.jauhiainen@gmail.com>
1 file changed