title: Proper way to fix a url without http://
body: <p>I'm trying to <code>open</code> a list of urls of this format, using in <code>Urllib2</code>:</p>
  
  <pre><code>google.com
  facebook.com
  youtube.com
  yahoo.com
  baidu.com
  </code></pre>
  
  <p>Using this method:</p>
  
  <p><code>urllib2.urlopen(url)</code>:</p>
  
  <p>And getting this error:</p>
  
  <pre><code>File "fetcher.py", line 98, in fetch_urls_and_save
    response = urllib2.urlopen(url)
  File "urllib2.py", line 154, in urlopen
    return opener.open(url, data, timeout)
  File "urllib2.py", line 423, in open
    protocol = req.get_type()
  File "urllib2.py", line 285, in get_type
    raise ValueError, "unknown url type: %s" % self.__original
  </code></pre>
  
  <p>So, my question is:</p>
  
  <p>Is there a proper way to 'fix' those urls, or should I simply append <code>http://</code> in front of every string? I don't think that would be the best solution, because what about the urls that begin with <code>https://</code>?</p>