Recent failure on AMD64 Debian root 3.7:

http://buildbot.python.org/all/#/builders/127/builds/361

0:03:33 load avg: 1.38 [140/415/1] test_signal failed

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FAIL: test_stress_delivery_dependent (test.test_signal.StressTest)
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Traceback (most recent call last):
  File "/root/buildarea/3.7.angelico-debian-amd64/build/Lib/test/test_signal.py", line 1116, in test_stress_delivery_dependent
    self.assertEqual(len(sigs), N, "Some signals were lost")
AssertionError: 3586 != 10000 : Some signals were lost

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FAIL: test_stress_delivery_simultaneous (test.test_signal.StressTest)
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Traceback (most recent call last):
  File "/root/buildarea/3.7.angelico-debian-amd64/build/Lib/test/test_signal.py", line 1149, in test_stress_delivery_simultaneous
    self.assertEqual(len(sigs), N, "Some signals were lost")
AssertionError: 8884 != 10000 : Some signals were lost