It looks like test_platform started to fail on AMD64 Windows10 3.x between build 1456 (success) and 1458 (failure, 1457 was interrupted or something like that).

The regression may be related to the issue #27932, change 31b7eaff5588.

http://buildbot.python.org/all/builders/AMD64%20Windows10%203.x/builds/1458/steps/test/logs/stdio

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FAIL: test_architecture_via_symlink (test.test_platform.PlatformTest)
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Traceback (most recent call last):
  File "D:\buildarea\3.x.bolen-windows10\build\lib\test\test_platform.py", line 33, in test_architecture_via_symlink
    self.assertEqual(get(real), get(link))
AssertionError: Tuples differ: (b"('64bit', 'WindowsPE')\r\n", None) != (b'', None)

First differing element 0:
b"('64bit', 'WindowsPE')\r\n"
b''

- (b"('64bit', 'WindowsPE')\r\n", None)
+ (b'', None)

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