.../infra/luci/appengine/swarming/swarming_bot/bot_code/task_runner_test.py (18.20s) failed
(...)
test_isolated_io_signal_no_grace_grand_children (__main__.TestTaskRunnerNoTimeMock)
Handles grand-children process hanging and signal management. ... FAIL
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FAIL: test_isolated_io_signal_no_grace_grand_children (__main__.TestTaskRunnerNoTimeMock)
Handles grand-children process hanging and signal management.
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Traceback (most recent call last):
  File ".../infra/luci/appengine/swarming/swarming_bot/bot_code/task_runner_test.py", line 1246, in test_isolated_io_signal_no_grace_grand_children
    self.assertEqual(2, len(to_kill))
AssertionError: 2 != 1
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