Index: Lib/test/pickletester.py
===================================================================
--- Lib/test/pickletester.py	(revision 62635)
+++ Lib/test/pickletester.py	(working copy)
@@ -585,7 +585,7 @@
             p = self.dumps(None, proto)
             self.assertEqual(p, expected)
 
-        oob = protocols[-1] + 1     # a future protocol
+        oob = list(protocols)[-1] + 1     # a future protocol
         badpickle = pickle.PROTO + bytes([oob]) + build_none
         try:
             self.loads(badpickle)