解决xpath中文乱码

利用xpath建标签树以后，虽然提高了元素匹配效率，但是etree会把中文转为ASCII码，所以简单地tostring以后会有乱码。

解决方法：

import requests
from requests.exceptions import RequestException
from lxml import etree

headers = {
    'User-Agent': 'Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14_2) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/12.0.2 Safari/605.1.15',
}

def get_one_page(url, headers):
    try:
        response = requests.get(url, headers=headers)
        if response.status_code == 200:
            response.encoding = response.apparent_encoding
            return response.text
        return None
    except RequestException:
        return None

tree = etree.HTML(html)
aim = tree.xpath(exp)
for i in aim:
    content = etree.tostring(i, encoding='utf-8', pretty_print=True, method="html").decode('utf-8')