diff --git a/Lib/functools.py b/Lib/functools.py
index cd374631f16792..e03a77f204b544 100644
--- a/Lib/functools.py
+++ b/Lib/functools.py
@@ -232,7 +232,7 @@ def __ge__(self, other):
 ### reduce() sequence to a single item
 ################################################################################
 
-_initial_missing = object()
+_initial_missing = sentinel('_initial_missing')
 
 def reduce(function, sequence, initial=_initial_missing):
     """