build fails on FreeBSD 11.1 about python-subprocess32 HOT 4 CLOSED

FAIL: test_close_fds_when_max_fd_is_lowered (__main__.POSIXProcessTestCase)
Confirm that issue21618 is fixed (may fail under valgrind).
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Traceback (most recent call last):
  File "<stdin>", line 1866, in test_close_fds_when_max_fd_is_lowered
AssertionError: Some fds were left open.
:
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FAIL: test_cloexec_pass_fds (__main__.POSIXSubprocessModuleTestCase)
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Traceback (most recent call last):
  File "<stdin>", line 2257, in test_cloexec_pass_fds
AssertionError: '' != 'cat: /dev/fd/4: No such file or directory\n'
:
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FAIL: test_close_fds_when_max_fd_is_lowered (__main__.ProcessTestCasePOSIXPurePython)
Confirm that issue21618 is fixed (may fail under valgrind).
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Traceback (most recent call last):
  File "<stdin>", line 1866, in test_close_fds_when_max_fd_is_lowered
AssertionError: Some fds were left open.
:
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Ran 291 tests in 253.214s
:
FAILED (failures=3, skipped=5)
Traceback (most recent call last):
  File "<stdin>", line 2420, in <module>
  File "<stdin>", line 2416, in test_main
  File "/usr/home/dima/Sage/sage/local/lib/python2.7/test/support/__init__.py", line 1577, in run_unittest
    _run_suite(suite)
  File "/usr/home/dima/Sage/sage/local/lib/python2.7/test/support/__init__.py", line 1542, in _run_suite
    raise TestFailed(err)
test.support.TestFailed: multiple errors occurred