Mais qui est derrière tout ça ?

>>> print urllib.urlopen('http://www.craigslist.org').info()
Cache-Control: public
Connection: close
Date: Thu, 23 Mar 2006 21:23:59 GMT
Server: Apache/1.3.34 (Unix) mod_gzip/1.3.26.1a mod_perl/1.29
Vary: Accept-Encoding
Content-Length: 31804
Content-Type: text/html; charset=utf-8
Expires: Thu, 23 Mar 2006 21:23:59 GMT
Last-Modified: Thu, 23 Mar 2006 21:23:59 GMT

>>> print urllib.urlopen('http://www.google.com').info()
Cache-Control: private
Content-Type: text/html
Set-Cookie: PREF=ID=8457b90495103bcf:TM=1143152253:LM=1143152253:S=RB2Q-0UP2rGwUI_D; expires=Sun, 17-Jan-2038 19:14:07 GMT; path=/; domain=.google.com
Server: GWS/2.1
Date: Thu, 23 Mar 2006 22:17:33 GMT
Connection: Close

Et donc on apprend que google utilise le GWS 2.1, qui doit etre le google web server. Merci python !!