def download(self,url):
        if url is None:
            return None
        print(url)
        respone = urllib.request.urlopen(url)
        print('222')
        if respone.get_code() != 200
            return None
        print('333')
        return respone.read()

第一个网址就爬取失败，定位到这一行挂掉了respone = urllib.request.urlopen(url)

网址没问题，换了其他也是如此

PS：我的是python3.4