Issue #4740: Use HIGHEST_PROTOCOL in pickle test. This enables test for protocol 3
(== HIGHEST_PROTOCOL in 3.x)
diff --git a/Lib/test/test_deque.py b/Lib/test/test_deque.py
index 1ac43da..7af0803 100644
--- a/Lib/test/test_deque.py
+++ b/Lib/test/test_deque.py
@@ -375,7 +375,7 @@
 
     def test_pickle(self):
         d = deque(range(200))
-        for i in (0, 1, 2):
+        for i in range(pickle.HIGHEST_PROTOCOL + 1):
             s = pickle.dumps(d, i)
             e = pickle.loads(s)
             self.assertNotEqual(id(d), id(e))
@@ -384,7 +384,7 @@
 ##    def test_pickle_recursive(self):
 ##        d = deque('abc')
 ##        d.append(d)
-##        for i in (0, 1, 2):
+##        for i in range(pickle.HIGHEST_PROTOCOL + 1):
 ##            e = pickle.loads(pickle.dumps(d, i))
 ##            self.assertNotEqual(id(d), id(e))
 ##            self.assertEqual(id(e), id(e[-1]))