python通过LXML库读取xml命名空间

xml实例版本：

　　<a>
　　　　<city:table xmlns:city="city">
        <heilongjiang name="citys"><city:haerbin/><city:daqing/></heilongjiang>
        <guangdong name="citys"><city:guangzhou/><city:shenzhen/><city:zhuhai/></guangdong>
        <taiwan name="citys"><city:taibei/><city:gaoxiong/></taiwan>
        <xinjiang name="citys"><city:wulumuqi> 晴</city:wulumuqi></xinjiang>
        </city:table>
　　</a>    

<city:table xmlns:city="city"></city:table>
声明命名空间，city为变量，xmlns定义city变量的值。
python 读取输出实例：

        xp=xpxlm.xpath('//node()')
        print xp,           #.items()#.tag
        for i in xp:
            if '' in i or '\n' in i:
                continue
            else:
                print i.tag

输出结果：

{city}table
heilongjiang
{city}haerbin
{city}daqing
guangdong
{city}guangzhou
{city}shenzhen
{city}zhuhai
........

改变<city:table xmlns:city="city">为

<city:table xmlns:city="a">
输出结果为：

{a}table
heilongjiang
{a}haerbin
{a}daqing
guangdong
{a}guangzhou
{a}shenzhen
{a}zhuhai
taiwan
{a}taibei
{a}gaoxiong
xinjiang
{a}wulumuqi