下载文件时python有自己的cookie吗

当我使用python下载web文件时。它得到

---------------------------服务器答复您没有下载此文件的权限

详细信息：HTTP/1.1 403禁止

但当我使用chrome网站点击链接时，可以毫无问题地下载。为什么?

如果是的话，我可以清洗一下吗。我的代码是：

#!/usr/bin/python  
#-*-coding:utf-8-*- 
import urllib2
import os
from subprocess import check_output
def data(url):
    
    
    
    up=urllib2.urlopen(url)
    
    cont=up.read()
    
    key1="http://videolectures.net/site/secure_dl/"
    key2=".mp4"
    
    pa=cont.find(key1)
    pt=cont.find(key2,pa)
    
    urlx=cont[pa:pt+4]
    
    return urlx
    
if __name__ == "__main__":  
    url_main=["http://videolectures.net/mit600f08_grimson_lec01/",
        "http://videolectures.net/mit600f08_grimson_lec02/",
        "http://videolectures.net/mit600f08_grimson_lec03/",
        "http://videolectures.net/mit600f08_grimson_lec04/",
        "http://videolectures.net/mit600f08_grimson_lec07/",
        "http://videolectures.net/mit600f08_grimson_lec08/",
        "http://videolectures.net/mit600f08_grimson_lec09/",
        "http://videolectures.net/mit600f08_grimson_lec10/",
        "http://videolectures.net/mit600f08_grimson_lec15/",
        "http://videolectures.net/mit600f08_grimson_lec16/",
        "http://videolectures.net/mit600f08_guttag_lec05/",
        "http://videolectures.net/mit600f08_guttag_lec06/",
        "http://videolectures.net/mit600f08_guttag_lec11/",
        "http://videolectures.net/mit600f08_guttag_lec12/",
        "http://videolectures.net/mit600f08_guttag_lec13/",
        "http://videolectures.net/mit600f08_guttag_lec14/",
        "http://videolectures.net/mit600f08_guttag_lec17/",
        "http://videolectures.net/mit600f08_guttag_lec18/",
        "http://videolectures.net/mit600f08_guttag_lec19/",
        "http://videolectures.net/mit600f08_guttag_lec20/",
        "http://videolectures.net/mit600f08_guttag_lec21/",
        "http://videolectures.net/mit600f08_guttag_lec22/",
        "http://videolectures.net/mit600f08_guttag_lec23/",
        "http://videolectures.net/mit600f08_guttag_lec24/"]
    file = open('file.txt', 'w')
    file.close()
    for url in url_main:
        
        print url
        url_video=data(url)
        file = open('file.txt', 'a')
        file.write(url_video+'\n')
        file.close()
        check_output("cmd.exe /k "+"\"C:\Program Files (x86)\Internet Download Manager\IDMan.exe\"  /d "+url_video, shell=True)  
    

---

您是对的，python有自己的cookie，您必须使用库，请参见下面的链接：