test_subprocess.POSIXProcessTestCase fails in AMD64 Ubuntu 3.x buildbots:

https://buildbot.python.org/all/#/builders/154/builds/104

It seems that it has some problems with (unclosed?) file descriptors:

test_terminate_dead (test.test_subprocess.Win32ProcessTestCase) ... skipped 'Windows specific tests'
======================================================================
FAIL: test_close_fds (test.test_subprocess.POSIXProcessTestCase)
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Traceback (most recent call last):
  File "/home/buildbot/buildarea/3.x.einat-ubuntu/build/Lib/test/test_subprocess.py", line 2378, in test_close_fds
    "Some fds were left open")
AssertionError: {3} is not false : Some fds were left open
======================================================================
FAIL: test_close_fds_after_preexec (test.test_subprocess.POSIXProcessTestCase)
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Traceback (most recent call last):
  File "/home/buildbot/buildarea/3.x.einat-ubuntu/build/Lib/test/test_subprocess.py", line 2653, in test_close_fds_after_preexec
    self.assertNotIn(fd, remaining_fds)
AssertionError: 3 unexpectedly found in {0, 1, 2, 3}
======================================================================
FAIL: test_pass_fds (test.test_subprocess.POSIXProcessTestCase)
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Traceback (most recent call last):
  File "/home/buildbot/buildarea/3.x.einat-ubuntu/build/Lib/test/support/__init__.py", line 615, in wrapper
    return func(*args, **kw)
  File "/home/buildbot/buildarea/3.x.einat-ubuntu/build/Lib/test/test_subprocess.py", line 2503, in test_pass_fds
    "fd to be closed passed")
AssertionError: {4} is not false : fd to be closed passed
----------------------------------------------------------------------
Ran 285 tests in 68.129s
FAILED (failures=3, skipped=28)
1 test failed again:
    test_subprocess