docs: def absolutify(url):
      """Takes a URL and prepends the SITE_URL"""
      site_url = getattr(settings, 'SITE_URL', False)
  
      # If we don't define it explicitly
      if not site_url:
          protocol = settings.PROTOCOL
          hostname = settings.DOMAIN
          port = settings.PORT
          if (protocol, port) in (('https://', 443), ('http://', 80)):
              site_url = ''.join(map(str, (protocol, hostname)))
          else:
              site_url = ''.join(map(str, (protocol, hostname, ':', port)))
  
      return site_url + url