diff -r 4617b7ac302a Lib/test/test_bisect.py
--- a/Lib/test/test_bisect.py	Tue Jan 08 11:27:18 2013 +0000
+++ b/Lib/test/test_bisect.py	Tue Jan 08 15:40:27 2013 -0600
@@ -3,25 +3,8 @@
 from test import support
 from collections import UserList
 
-# We do a bit of trickery here to be able to test both the C implementation
-# and the Python implementation of the module.
-
-# Make it impossible to import the C implementation anymore.
-sys.modules['_bisect'] = 0
-# We must also handle the case that bisect was imported before.
-if 'bisect' in sys.modules:
-    del sys.modules['bisect']
-
-# Now we can import the module and get the pure Python implementation.
-import bisect as py_bisect
-
-# Restore everything to normal.
-del sys.modules['_bisect']
-del sys.modules['bisect']
-
-# This is now the module with the C implementation.
-import bisect as c_bisect
-
+py_bisect = support.import_fresh_module('bisect', blocked=['_bisect'])
+c_bisect = support.import_fresh_module('bisect', fresh=['_bisect'])
 
 class Range(object):
     """A trivial range()-like object without any integer width limitations."""
@@ -45,9 +28,7 @@
         self.last_insert = idx, item
 
 
-class TestBisect(unittest.TestCase):
-    module = None
-
+class TestBisect:
     def setUp(self):
         self.precomputedCases = [
             (self.module.bisect_right, [], 1, 0),
@@ -218,17 +199,15 @@
         self.module.insort(a=data, x=25, lo=1, hi=3)
         self.assertEqual(data, [10, 20, 25, 25, 25, 30, 40, 50])
 
-class TestBisectPython(TestBisect):
+class TestBisectPython(TestBisect, unittest.TestCase):
     module = py_bisect
 
-class TestBisectC(TestBisect):
+class TestBisectC(TestBisect, unittest.TestCase):
     module = c_bisect
 
 #==============================================================================
 
-class TestInsort(unittest.TestCase):
-    module = None
-
+class TestInsort:
     def test_vsBuiltinSort(self, n=500):
         from random import choice
         for insorted in (list(), UserList()):
@@ -255,10 +234,10 @@
         self.module.insort_right(lst, 5)
         self.assertEqual([5, 10], lst.data)
 
-class TestInsortPython(TestInsort):
+class TestInsortPython(TestInsort, unittest.TestCase):
     module = py_bisect
 
-class TestInsortC(TestInsort):
+class TestInsortC(TestInsort, unittest.TestCase):
     module = c_bisect
 
 #==============================================================================
@@ -284,9 +263,7 @@
     __eq__ = __lt__
     __ne__ = __lt__
 
-class TestErrorHandling(unittest.TestCase):
-    module = None
-
+class TestErrorHandling:
     def test_non_sequence(self):
         for f in (self.module.bisect_left, self.module.bisect_right,
                   self.module.insort_left, self.module.insort_right):
@@ -313,10 +290,10 @@
                   self.module.insort_left, self.module.insort_right):
             self.assertRaises(TypeError, f, 10)
 
-class TestErrorHandlingPython(TestErrorHandling):
+class TestErrorHandlingPython(TestErrorHandling, unittest.TestCase):
     module = py_bisect
 
-class TestErrorHandlingC(TestErrorHandling):
+class TestErrorHandlingC(TestErrorHandling, unittest.TestCase):
     module = c_bisect
 
 #==============================================================================