title: Python mechanize login Facebook, use beautifulshoup get profile picture failed
body: <p>I'm trying to keep login Facebook using Python mechanize library and get Zuck's profile picture url using BeautifulSoup. Here is my code:</p>
  
  <pre><code>import cookielib
  import mechanize
  from BeautifulSoup import BeautifulSoup
  
  # Browser
  br = mechanize.Browser()
  
  # Enable cookie support for urllib2
  cookiejar = cookielib.LWPCookieJar()
  br.set_cookiejar(cookiejar)
  
  # Broser options
  br.set_handle_equiv(True)
  br.set_handle_gzip(True)
  br.set_handle_redirect(True)
  br.set_handle_referer(True)
  br.set_handle_robots(False)
  
  #
  br.set_handle_refresh(mechanize._http.HTTPRefreshProcessor(), max_time=1)
  
  br.addheaders = [('User-agent', 'Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.9.0.1) Gecko/2008071615 Fedora/3.0.1-1.fc9 Firefox/3.0.1')]
  
  # authenticate
  br.open('https://www.facebook.com/')
  br.select_form(nr=0)
  # these two come from the code you posted
  # where you would normally put in your username and password
  br['email'] = 'my_email_address'
  br['pass'] = 'my_password'
  res = br.submit()
  
  print "Success!\n"
  
  url = 'https://www.facebook.com/zuck'
  soup = BeautifulSoup(br.open(url).read())
  # print soup
  print [x for x in soup.findAll('img', {'class': 'profilePic img'})]
  </code></pre>
  
  <p>However, the html that BeautifulSoup read is not Zuck's Facebook homepage source code. The html starts with </p>
  
  <pre><code>&lt;html lang="zh-Hans" id="facebook" class="no_js"&gt;...
  </code></pre>
  
  <p>It contains no 'img' with class = 'profilePic img' I need. What's the problem? Thanks!</p>