docs: def update(url):
      """
      Update remote DNS record by requesting its special endpoint URL.
  
      This automatically picks the IP address using the HTTP connection: it is not
      possible to specify the IP address explicitly.
  
      :param url: URL to retrieve for triggering the update
      :return: IP address
      """
      req = requests.get(
          url, headers=constants.REQUEST_HEADERS_DEFAULT, timeout=60)
      req.close()
      # Response must contain an IP address, or else we can't parse it.
      # Also, the IP address in the response is the newly assigned IP address.
      ipregex = re.compile(r"\b(?P<ip>(?:[0-9]{1,3}\.){3}[0-9]{1,3})\b")
      ipmatch = ipregex.search(req.text)
      if ipmatch:
          return str(ipaddress(ipmatch.group("ip")))
      LOG.error("couldn't parse the server's response '%s'", req.text)
      return None