import requests as r
from lxml import etree
import re,os,random,time

url='http://xxx.com/xx'

res=r.get(url)
html=etree.HTML(res.text)

title=html.xpath('//title/text()')

lis=html.xpath('//ul[@class="viewlist_ul"]/li[@name="lazyloadcpc"]')
print('共得到车个数:',len(lis))

cars=[]
for li in lis:
    name=li.xpath('.//h4[@class="card-name"]/text()')[0]  #【从当前节点取数据要用】 .//

    zonghe=li.xpath('.//p[@class="cards-unit"]/text()')[0]
    zh=re.findall(r'(.*?)/(.*?)/(.*?)/(.*)',zonghe)
    licheng=zh[0][0].replace('万公里','')
    year=zh[0][1]
    address=zh[0][2]
    shangjia=zh[0][3]

    price=li.xpath('.//span[@class="pirce"]//text()')
    price=price[-1] if price[-2]=='抢购价' else price[-2] #如果内部有抢购价则价格取-1,否则取-2

    price2=li.xpath('.//div[@class="cards-price-box"]/s/text()')[0]

    tag=li.xpath('.//div[@class="cards-price-box"]/span[@class="tags"]/i/text()')
    tag=tag[0] if tag else '' #如果tag存在内容则=tag[0],否则=''

    cars.append({'车名':name,'里程':licheng,'年份':year,'地址':address,'商家':shangjia,
        '价格':price,'原价':price2,'其它':tag
        })

print(cars)