diff --git a/Lib/sets.py b/Lib/sets.py
index 069be64a7df..5f0f0a2d38c 100644
--- a/Lib/sets.py
+++ b/Lib/sets.py
@@ -177,7 +177,7 @@ class BaseSet(object):
             little, big = self, other
         else:
             little, big = other, self
-        common = filter(big._data.has_key, little._data.iterkeys())
+        common = filter(big._data.has_key, little._data)
         return self.__class__(common)
 
     def intersection(self, other):