python下载文件的三种方法

Python开发中时长遇到要下载文件的情况，最常用的方法就是通过Http利用urllib或者urllib2模块。 当然你也可以利用ftplib从ftp站点下载文件。此外Python还提供了另外一种方法requests。 下面来看看三种方法是如何来下载zip文件的：

方法一：

import urllib 
import urllib2 
import requests
print "downloading with urllib" 
url = 'https://www.codingsky.com/test/demo.zip'
print "downloading with urllib"
urllib.urlretrieve(url, "demo.zip")

方法二：

import urllib2
print "downloading with urllib2"
url = 'https://www.codingsky.com/test/demo.zip' 
f = urllib2.urlopen(url) 
data = f.read() 
with open("demo2.zip", "wb") as code:     
    code.write(data)

方法三：

import requests 
print "downloading with requests"
url = 'https://www.codingsky.com/test/demo.zip' 
r = requests.get(url) 
with open("demo3.zip", "wb") as code:
     code.write(r.content)