diff --git a/Lib/http/cookiejar.py b/Lib/http/cookiejar.py
index 97383d603e6..a516d735b8a 100644
--- a/Lib/http/cookiejar.py
+++ b/Lib/http/cookiejar.py
@@ -1,4 +1,4 @@
-"""HTTP cookie handling for web clients.
+r"""HTTP cookie handling for web clients.
 
 This module has (now fairly distant) origins in Gisle Aas' Perl module
 HTTP::Cookies, from the libwww-perl library.