PEP 3114: rename .next() to .__next__() and add next() builtin.
diff --git a/Lib/UserDict.py b/Lib/UserDict.py
index 91508d8..bcee543 100644
--- a/Lib/UserDict.py
+++ b/Lib/UserDict.py
@@ -139,7 +139,7 @@
         return value
     def popitem(self):
         try:
-            k, v = self.iteritems().next()
+            k, v = next(self.iteritems())
         except StopIteration:
             raise KeyError, 'container is empty'
         del self[k]