按照視屏編寫代碼，但是就是沒有運(yùn)行結(jié)果（正確的運(yùn)行結(jié)果會(huì)得到一個(gè)有內(nèi)容的txt文件，但是我所得到的txt文件時(shí)一個(gè)空的）。請各位指教

下面是代碼：
stocks.py

# -*- coding: utf-8 -*-
import scrapy
import re

class StocksSpider(scrapy.Spider):
    name = 'stocks'
    start_urls = ['http://quote.eastmoney.com/stocklist.html']

    def parse(self, response):#由start_urls經(jīng)過默認(rèn)的request方法爬取下來的response對象
        headers = {
          'Accept-Encoding':'gzip, deflate, sdch, br',
          'Accept-Language':'zh-CN,zh;q=0.8',
          'Connection':'keep-alive',
          'Referer':'https://gupiao.baidu.com/',
          'User-Agent':ua
          }
        for href in response.css("a::attr(href)").extract():#獲取的是href的屬性值
            try:
                stock=re.findall(r"[s][zh]\d{6}",href)[0]#獲取股票代碼
                url="http:/gupiao.baidu.com/stock/"+"".join(stock)+".html"#構(gòu)建一個(gè)百度股票代碼
                yield scrapy.Request(url,callback=self.parse_stock,headers=headers)#產(chǎn)生生成器,Request將response修改為新生成的與百度相關(guān)的連接
            except:
                continue
    def parse_stock(self,response):
        infoDict={}
        stockInfo=response.css(".stock-bets")
        name=stockInfo.css(".bets-name").extract()[0]
        keyList=stockInfo.css("dt").extract()#獲取文本內(nèi)容
        valueList=stockInfo.css("dd").extract()
        for i in range(len(keyList)):
            key=re.findall(r">.*</dt>",keyList[i])[0][1:-5]
            try:
                val=re.findall(r"\d\.?.*<\dd>",valueList[i])[0][0:-5]
            except:
                val="--"
            infoDict[key]=val

        infoDict.update({'股票名稱': re.findall('\s.*\(',name)[0].split()[0] +re.findall('\>.*\<', name)[0][1:-1]})
        yield infoDict

piplines.py

# -*- coding: utf-8 -*-

# Define your item pipelines here
#
# Don't forget to add your pipeline to the ITEM_PIPELINES setting
# See: https://doc.scrapy.org/en/latest/topics/item-pipeline.html


class BaiduscrapyPipeline(object):
    def process_item(self, item, spider):
        return item
class BaidustockInfoPipline(object):
    def open_spider(self,spider):#啟動(dòng)自動(dòng)調(diào)用爬蟲時(shí)的方法
        self.f=open("BaiduStockInfo.txt","w")
    def close_spider(self,spider):#關(guān)閉時(shí)自動(dòng)調(diào)用
        self.f.close()
    def process_item(self,item,spider):#對每一個(gè)item處理時(shí)調(diào)用
        try:
            line=str(dict(item))+"\n"
            self.f.write(line)
        except:
            pass
        return item

settings.py

BOT_NAME = 'BaiduScrapy'
SPIDER_MODULES = ['BaiduScrapy.spiders']
NEWSPIDER_MODULE = 'BaiduScrapy.spiders'
ROBOTSTXT_OBEY = True
ITEM_PIPELINES = {
    'BaiduScrapy.pipelines.BaidustockInfoPipline': 300,
}

執(zhí)行結(jié)果：

2018-01-30 19:33:13 [scrapy.utils.log] INFO: Scrapy 1.5.0 started (bot: BaiduScrapy)
2018-01-30 19:33:13 [scrapy.utils.log] INFO: Versions: lxml 4.1.1.0, libxml2 2.9.5, cssselect 1.0.3, parsel 1.3.1, w3lib 1.19.0, Twisted 17.9.0, Python 3.6.4 (v3.6.4:d48eceb, Dec 19 2017, 06:54:40) [MSC v.1900 64 bit (AMD64)], pyOpenSSL 17.5.0 (OpenSSL 1.1.0g  2 Nov 2017), cryptography 2.1.4, Platform Windows-10-10.0.14393-SP0
2018-01-30 19:33:13 [scrapy.crawler] INFO: Overridden settings: {'BOT_NAME': 'BaiduScrapy', 'NEWSPIDER_MODULE': 'BaiduScrapy.spiders', 'ROBOTSTXT_OBEY': True, 'SPIDER_MODULES': ['BaiduScrapy.spiders']}
2018-01-30 19:33:13 [scrapy.middleware] INFO: Enabled extensions:
['scrapy.extensions.corestats.CoreStats',
 'scrapy.extensions.telnet.TelnetConsole',
 'scrapy.extensions.logstats.LogStats']
2018-01-30 19:33:13 [scrapy.middleware] INFO: Enabled downloader middlewares:
['scrapy.downloadermiddlewares.robotstxt.RobotsTxtMiddleware',
 'scrapy.downloadermiddlewares.httpauth.HttpAuthMiddleware',
 'scrapy.downloadermiddlewares.downloadtimeout.DownloadTimeoutMiddleware',
 'scrapy.downloadermiddlewares.defaultheaders.DefaultHeadersMiddleware',
 'scrapy.downloadermiddlewares.useragent.UserAgentMiddleware',
 'scrapy.downloadermiddlewares.retry.RetryMiddleware',
 'scrapy.downloadermiddlewares.redirect.MetaRefreshMiddleware',
 'scrapy.downloadermiddlewares.httpcompression.HttpCompressionMiddleware',
 'scrapy.downloadermiddlewares.redirect.RedirectMiddleware',
 'scrapy.downloadermiddlewares.cookies.CookiesMiddleware',
 'scrapy.downloadermiddlewares.httpproxy.HttpProxyMiddleware',
 'scrapy.downloadermiddlewares.stats.DownloaderStats']
2018-01-30 19:33:13 [scrapy.middleware] INFO: Enabled spider middlewares:
['scrapy.spidermiddlewares.httperror.HttpErrorMiddleware',
 'scrapy.spidermiddlewares.offsite.OffsiteMiddleware',
 'scrapy.spidermiddlewares.referer.RefererMiddleware',
 'scrapy.spidermiddlewares.urllength.UrlLengthMiddleware',
 'scrapy.spidermiddlewares.depth.DepthMiddleware']
2018-01-30 19:33:13 [scrapy.middleware] INFO: Enabled item pipelines:
['BaiduScrapy.pipelines.BaidustockInfoPipline']
2018-01-30 19:33:13 [scrapy.core.engine] INFO: Spider opened
2018-01-30 19:33:13 [scrapy.extensions.logstats] INFO: Crawled 0 pages (at 0 pages/min), scraped 0 items (at 0 items/min)
2018-01-30 19:33:13 [scrapy.extensions.telnet] DEBUG: Telnet console listening on 127.0.0.1:6023
2018-01-30 19:33:13 [scrapy.downloadermiddlewares.redirect] DEBUG: Redirecting (meta refresh) to <GET http://www.eastmoney.com> from <GET http://quote.eastmoney.com/robots.txt>
2018-01-30 19:33:14 [scrapy.core.engine] DEBUG: Crawled (200) <GET http://www.eastmoney.com> (referer: None)
2018-01-30 19:33:14 [scrapy.core.engine] DEBUG: Crawled (200) <GET http://quote.eastmoney.com/stocklist.html> (referer: None)
2018-01-30 19:33:14 [scrapy.core.scraper] ERROR: Spider error processing <GET http://quote.eastmoney.com/stocklist.html> (referer: None)
Traceback (most recent call last):
  File "e:\software\python36\lib\site-packages\scrapy\utils\defer.py", line 102, in iter_errback
    yield next(it)
  File "e:\software\python36\lib\site-packages\scrapy\spidermiddlewares\offsite.py", line 30, in process_spider_output
    for x in result:
  File "e:\software\python36\lib\site-packages\scrapy\spidermiddlewares\referer.py", line 339, in <genexpr>
    return (_set_referer(r) for r in result or ())
  File "e:\software\python36\lib\site-packages\scrapy\spidermiddlewares\urllength.py", line 37, in <genexpr>
    return (r for r in result or () if _filter(r))
  File "e:\software\python36\lib\site-packages\scrapy\spidermiddlewares\depth.py", line 58, in <genexpr>
    return (r for r in result or () if _filter(r))
  File "F:\GitHubCode\Code\Python\BaiduScrapy\BaiduScrapy\spiders\stocks.py", line 15, in parse
    'User-Agent':ua
NameError: name 'ua' is not defined
2018-01-30 19:33:14 [scrapy.core.engine] INFO: Closing spider (finished)
2018-01-30 19:33:14 [scrapy.statscollectors] INFO: Dumping Scrapy stats:
{'downloader/request_bytes': 676,
 'downloader/request_count': 3,
 'downloader/request_method_count/GET': 3,
 'downloader/response_bytes': 686187,
 'downloader/response_count': 3,
 'downloader/response_status_count/200': 2,
 'downloader/response_status_count/404': 1,
 'finish_reason': 'finished',
 'finish_time': datetime.datetime(2018, 1, 30, 11, 33, 14, 925090),
 'log_count/DEBUG': 4,
 'log_count/ERROR': 1,
 'log_count/INFO': 7,
 'response_received_count': 2,
 'scheduler/dequeued': 1,
 'scheduler/dequeued/memory': 1,
 'scheduler/enqueued': 1,
 'scheduler/enqueued/memory': 1,
 'spider_exceptions/NameError': 1,
 'start_time': datetime.datetime(2018, 1, 30, 11, 33, 13, 484838)}
2018-01-30 19:33:14 [scrapy.core.engine] INFO: Spider closed (finished)