def test_captureSIGTERM(self):
        """
        ReactorBase's SIGTERM handler saves the value of SIGTERM to the
        _exitSignal attribute.
        """
        reactor = TestSpySignalCapturingReactor()
        reactor.sigTerm(signal.SIGTERM, None)
        self.assertEquals(signal.SIGTERM, reactor._exitSignal)

        ReactorBase's SIGTERM handler saves the value of SIGTERM to the
        _exitSignal attribute.
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/internet/test/test_base.py