python页面加载完

我尝试了下面的代码，但它总是在得到大小之前返回。在# config.url = 'http://www.neimanmarcus.com/Stuart-Weitzman-Reserve-Suede-Over-the-Knee-Boot-Black/prod179890262/p.prod'

import urllib2

import requests

import config

import time

from lxml.cssselect import CSSSelector

from lxml.html import fromstring

print config.url

headers = {

"Host": "www.neimanmarcus.com",

"Connection": "keep-alive",

"Content-Length": 106,

"Pragma": "no-cache",

"Cache-Control": "no-cache",

"Accept": "*/*",

"Origin": "http://www.neimanmarcus.com",

"X-Requested-With": "XMLHttpRequest",

"User-Agent": "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_10_5) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/50.0.2661.94 Safari/537.36",

"Content-Type": "application/x-www-form-urlencoded; charset=UTF-8",

"Referer": "http://www.neimanmarcus.com/Stuart-Weitzman-Reserve-Suede-Over-the-Knee-Boot-Black/prod179890262/p.prod",

"Accept-Language": "en-US,en;q=0.8,zh-CN;q=0.6,zh;q=0.4,fr;q=0.2,cs;q=0.2,zh-TW;q=0.2"

}

request = urllib2.Request(config.url, headers=headers)

html = urllib2.urlopen(request)

time.sleep(10)

html = html.read()

print html

html = fromstring(html)

sel = CSSSelector('option.addedOption')

try:

options = sel(html)

print options

except Exception as e:

print e

如何获得整个页面的信息(尤其是启动大小)？在