scrapy一直出现302

# -*- coding: utf-8 -*-
import scrapy
from scrapy.linkextractors import LinkExtractor
from scrapy.spiders import CrawlSpider, Rule
from scrapy import Request
from jingdong.items import JingdongItem
import re
import urllib.request
class JdSpider(CrawlSpider):
    name = 'jd'
    headers={"User-Agent","Mozilla/5.0 (Windows NT 10.0; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/57.0.2987.8 Safari/537.36"}
    allowed_domains = ['jd.com']
    start_urls = ['http://jd.com/']
    def start_requests(self):
        for url in self.start_urls:
            yield Request(url, cookies={'jd.com': 'False'})

    rules = (
        Rule(LinkExtractor(allow=''), callback='parse_item', follow=True),
    )

    def parse_item(self, response):
        try:
            i = JingdongItem()
            thisurl=response.url
            pat="item.jd.com/(.?*).html"
            x=re.search(pat,thisurl)
            if(x):
                thisid=compile(x).findall(thisurl)[0]
                title = response.xpath("//li[@class='img-hover']/img/@alt").extract()
                shop = response.xpath("//div[@class='name']/a[@target='_blank']/text()").extract()
                shopurl = response.xpath("//div[@class='name'']/a/@href").extract()
                print(title)
                print(shop)
                print(shopurl)
                priceurl="https://p.3.cn/prices/mgets%3F ... hisid
                commenturl="https://club.jd.com/comment/pr ... ot%3B
                pricedata=urllib.request.urlopen(priceurl).read().decode("utf-8","ignore")
                commentdata=urllib.request.urlopen(commenturl).read().decode("urf-8","ignore")
                pricepat='"p":"(.?*)"'
                commentpat='"goodRateShow":(.?*),"'
                price=compile(pricedata).findall(pricepat)[0]
                comment=compile(commentdata).findall(commentpat)[0]
                if(len(title) and len(shop) and len(shopurl) and len(price) and len(comment)):
                    print(title[0])
                    print(shop[0])
                    print(shopurl[0])
                    print(price[0])
                    price(comment[0])
                    print("------------")
                else:
                    pass

            return i
        except Exception as e:
            print(e)