def test_killESRCH(self):
        """
        L{lockfile.kill} raises L{OSError} with errno of L{ESRCH} if
        passed a PID which does not correspond to any process.
        """
        # Hopefully there is no process with PID 2 ** 31 - 1
        exc = self.assertRaises(OSError, lockfile.kill, 2 ** 31 - 1, 0)
        self.assertEqual(exc.errno, errno.ESRCH)

        L{lockfile.kill} raises L{OSError} with errno of L{ESRCH} if
        passed a PID which does not correspond to any process.
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/test/test_lockfile.py