Python - alter user agent string in web request

# Sometimes websites deny access to bots or unsupported browsers
# python allows you to change the user agent string so you can 
# impersonate any browser you desire

import urllib
import urllib2

# unaltered header.

print "sending a request using the default python user agent string..."
url = 'http://www.example.com'
req = urllib2.Request(url)

response = urllib2.urlopen(req)
the_page = response.read()


# alter the header to look like a real browser
print "sending a request with an altered user agent string..."
url = 'http://www.example.com'
user_agent = 'Mozilla/4.0 (compatible; MSIE 5.5; Windows NT)'

headers = { 'User-Agent' : user_agent }
req = urllib2.Request(url, data=None, headers=headers) #, data) #, headers)

response = urllib2.urlopen(req)
the_page = response.read()



#Apache logs on the server indicate:
#   make a request without altering the user_agent
#       "POST / HTTP/1.1" 200 2022 "-" "Python-urllib/2.6"
#
#   a request made with the altered user_agent
#       "POST / HTTP/1.1" 200 2022 "-" "Mozilla/4.0 (compatible; MSIE 5.5; Windows NT)"