def test_portRangeInheritedFromFactory(self):
        """
        The L{FTP} instances created by L{ftp.FTPFactory.buildProtocol} have
        their C{passivePortRange} attribute set to the same object the
        factory's C{passivePortRange} attribute is set to.
        """
        portRange = range(2017, 2031)
        self.factory.passivePortRange = portRange
        protocol = self.factory.buildProtocol(None)
        self.assertEqual(portRange, protocol.wrappedProtocol.passivePortRange)

        The L{FTP} instances created by L{ftp.FTPFactory.buildProtocol} have
        their C{passivePortRange} attribute set to the same object the
        factory's C{passivePortRange} attribute is set to.
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/test/test_ftp.py