def test_outputSignal(self):
        """
        If the child process exits because of a signal, the L{Deferred}
        returned by L{getProcessOutputAndValue} fires a L{Failure} of a tuple
        containing the child's stdout, stderr, and the signal which caused
        it to exit.
        """
        # Use SIGKILL here because it's guaranteed to be delivered. Using
        # SIGHUP might not work in, e.g., a buildbot slave run under the
        # 'nohup' command.
        scriptFile = self.makeSourceFile([
            "import sys, os, signal",
            "sys.stdout.write('stdout bytes\\n')",
            "sys.stderr.write('stderr bytes\\n')",
            "sys.stdout.flush()",
            "sys.stderr.flush()",
            "os.kill(os.getpid(), signal.SIGKILL)"])

        def gotOutputAndValue(out_err_sig):
            out, err, sig = out_err_sig
            self.assertEqual(out, b"stdout bytes\n")
            self.assertEqual(err, b"stderr bytes\n")
            self.assertEqual(sig, signal.SIGKILL)

        d = utils.getProcessOutputAndValue(self.exe, ['-u', scriptFile])
        d = self.assertFailure(d, tuple)
        return d.addCallback(gotOutputAndValue)

        If the child process exits because of a signal, the L{Deferred}
        returned by L{getProcessOutputAndValue} fires a L{Failure} of a tuple
        containing the child's stdout, stderr, and the signal which caused
        it to exit.
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/test/test_iutils.py