[2.7] advance copyright years to 2018 (GH-5094). (#5105)

(cherry picked from commit 65f2a6dcc2bc28a8566b74c8e9273f982331ec48)
diff --git a/Python/getcopyright.c b/Python/getcopyright.c
index c37f8fa..1b69012 100644
--- a/Python/getcopyright.c
+++ b/Python/getcopyright.c
@@ -4,7 +4,7 @@
 
 static char cprt[] = 
 "\
-Copyright (c) 2001-2017 Python Software Foundation.\n\
+Copyright (c) 2001-2018 Python Software Foundation.\n\
 All Rights Reserved.\n\
 \n\
 Copyright (c) 2000 BeOpen.com.\n\