我想去猜演唱會門票的購買URL, 使用 requests 來判斷 url 是否存在，遇到 server side 會使用 http code 302 來 redirect.

解法：

The response.history attribute is a list of responses that led to the final URL, which can be found in response.url.

response = requests.get(someurl)
if response.history:
    print "Request was redirected"
    for
 
 resp in response.history:
        print resp.status_code, resp.url
    print "Final destination:"
    print response.status_code, response.url
else:
    print "Request was not redirected"

Demo:

>>> import requests
>>> response = requests.get('http://httpbin.org/redirect/3')
>>>
 
 response.history
(<Response [302]>, <Response [302]>, <Response [302]>)
>>> for resp in response.history:
...     print resp.status_code, resp.url
... 
302 http://httpbin.org/redirect/3
302 http://httpbin.org/redirect/2
302 http://httpbin.org/redirect/1
>>> print response.
 
status_code, response.url
200 http://httpbin.org/get