def test_secureConnection(self):
        """
        L{_ExistingConnectionHelper.secureConnection} returns a L{Deferred}
        which fires with whatever object was fed to
        L{_ExistingConnectionHelper.__init__}.
        """
        result = object()
        helper = _ExistingConnectionHelper(result)
        self.assertIs(
            result, self.successResultOf(helper.secureConnection()))

        L{_ExistingConnectionHelper.secureConnection} returns a L{Deferred}
        which fires with whatever object was fed to
        L{_ExistingConnectionHelper.__init__}.
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/conch/test/test_endpoints.py