Instead of scraping for the last modified date, you could read the last-modified header from the request:

```python
import urllib2
request = urllib2.Request('http://mirrors.jenkins-ci.org/war-stable/1.509.4/jenkins.war')
opener = urllib2.build_opener()
firstdatastream = opener.open(request)
firstdatastream.headers.get('Last-Modified')  # 'Wed, 09 Oct 2013 17:46:29 GMT'
```