def demo(host, user, expr):
    with manager.connect(host=host, port=22, username=user) as m:
        assert(":xpath" in m.server_capabilities)
        c = m.get_config(source='running', filter=('xpath', expr)).data_xml
        with open("%s.xml" % host, 'w') as f:
            f.write(c)
dataset/ETHPy150Open ncclient/ncclient/examples/nc03.py/demo/original