def test_getLogObserverDontOverrideSignalHandler(self):
        def fakeGetSignal(sig):
            self.assertEqual(sig, signal.SIGUSR1)
            return object()
        self.patch(signal, "getsignal", fakeGetSignal)
        filename = self.mktemp()
        logger = UnixAppLogger({"logfile": filename})
        logger._getLogObserver()

        self.assertEqual(self.signals, [])
If a signal handler is already installed,
dataset/ETHPy150Open twisted/twisted/twisted/test/test_twistd.py/UnixAppLoggerTests.test_getLogObserverDontOverrideSignalHandler