test_os fails on Windows since the changeset 75aadb4450fd:
http://buildbot.python.org/all/builders/AMD64%20Windows7%20SP1%203.x/builds/5798/steps/test/logs/stdio

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FAIL: test_15261 (test.test_os.StatAttributeTests)
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Traceback (most recent call last):
  File "C:\buildbot.python.org\3.x.kloth-win64\build\lib\test\test_os.py", line 581, in test_15261
    self.assertEqual(ctx.exception.errno, errno.EBADF)
AssertionError: 22 != 9

======================================================================
FAIL: test_fstat (test.test_os.TestInvalidFD)
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Traceback (most recent call last):
  File "C:\buildbot.python.org\3.x.kloth-win64\build\lib\test\test_os.py", line 1378, in check
    f(support.make_bad_fd(), *args)
FileNotFoundError: [WinError 18] There are no more files

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "C:\buildbot.python.org\3.x.kloth-win64\build\lib\test\test_os.py", line 1371, in helper
    self.check(getattr(os, f))
  File "C:\buildbot.python.org\3.x.kloth-win64\build\lib\test\test_os.py", line 1380, in check
    self.assertEqual(e.errno, errno.EBADF)
AssertionError: 2 != 9