The test fails on Python 3.5 but pass on Python 3.6, I don't know why.

http://buildbot.python.org/all/builders/x86-64%20El%20Capitan%203.5/builds/31/steps/test/logs/stdio

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ERROR: testFDPassEmpty (test.test_socket.RecvmsgSCMRightsStreamTest)
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Traceback (most recent call last):
  File "/Users/buildbot/buildarea/3.5.billenstein-elcapitan/build/Lib/test/test_socket.py", line 2851, in testFDPassEmpty
    len(MSG), 10240),
  File "/Users/buildbot/buildarea/3.5.billenstein-elcapitan/build/Lib/test/test_socket.py", line 1955, in doRecvmsg
    result = sock.recvmsg(bufsize, *args)
OSError: [Errno 12] Cannot allocate memory

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ERROR: testFDPassEmpty (test.test_socket.RecvmsgIntoSCMRightsStreamTest)
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Traceback (most recent call last):
  File "/Users/buildbot/buildarea/3.5.billenstein-elcapitan/build/Lib/test/test_socket.py", line 2851, in testFDPassEmpty
    len(MSG), 10240),
  File "/Users/buildbot/buildarea/3.5.billenstein-elcapitan/build/Lib/test/test_socket.py", line 2046, in doRecvmsg
    result = sock.recvmsg_into([buf], *args)
OSError: [Errno 12] Cannot allocate memory