Various tests cleanup: check_warnings/check_py3k_warnings, unittest.assert* and setUp/tearDown.
diff --git a/Lib/test/test_bytes.py b/Lib/test/test_bytes.py
index 70cab1c..3f8402c 100644
--- a/Lib/test/test_bytes.py
+++ b/Lib/test/test_bytes.py
@@ -841,9 +841,9 @@
         self.assertEqual(bytes(b"abc") <= b"ab", False)
 
     def test_doc(self):
-        self.assertTrue(bytearray.__doc__ != None)
+        self.assertIsNotNone(bytearray.__doc__)
         self.assertTrue(bytearray.__doc__.startswith("bytearray("), bytearray.__doc__)
-        self.assertTrue(bytes.__doc__ != None)
+        self.assertIsNotNone(bytes.__doc__)
         self.assertTrue(bytes.__doc__.startswith("bytes("), bytes.__doc__)
 
     def test_from_bytearray(self):