diff --git a/Lib/urllib/parse.py b/Lib/urllib/parse.py
index d64f678d235b6f..82b95adbdc283e 100644
--- a/Lib/urllib/parse.py
+++ b/Lib/urllib/parse.py
@@ -277,7 +277,7 @@ def _hostinfo(self):
         return hostname, port
 
 
-_UNSPECIFIED = ['not specified']
+_UNSPECIFIED = sentinel("_UNSPECIFIED", repr="<not specified>")
 _MISSING_AS_NONE_DEFAULT = False
 
 class _ResultBase: