code: def get(url, last_modified=None):
      
      try:
          with closing(urllib2.urlopen(url)) as page:
              if last_modified is not None:
                  last_mod = dateutil.parser.parse(dict(page.info())['last-modified'])
                  if last_mod <= last_modified:
                      return ""
              return page.read()
      except urllib2.URLError:
          return ""
docs: Performs a get request to a given url. Returns an empty str on error.