They didn't mention this in python documentation. And recently I'm testing a website simply refreshing the site using urllib2.urlopen() to extract certain content, I notice sometimes when I update the site urllib2.urlopen() seems not get the newly added content. So I wonder it does cache stuff somewhere, right?
I find it hard to believe that urllib2 does not do caching, because in my case, upon restart of the program the data is refreshed. If the program is not restarted, the data appears to be cached forever. Also retrieving the same data from Firefox never returns stale data.
Does urllib2.urlopen() cache stuff?