Issue #16443: Add docstrings to regular expression match objects.

Patch by Anton Kasyanov.
diff --git a/Misc/ACKS b/Misc/ACKS
index 81af9fd..f9c75ab 100644
--- a/Misc/ACKS
+++ b/Misc/ACKS
@@ -543,6 +543,7 @@
 Rafe Kaplan
 Jacob Kaplan-Moss
 Jan Kaliszewski
+Anton Kasyanov
 Lou Kates
 Hiroaki Kawai
 Sebastien Keim