docs: def __get_resource(dao, url):
      """
      Issue a GET request to IASystem with the given url
      and return a response in Collection+json format.
      :returns: http response with content in json
      """
      headers = {"Accept": "application/vnd.collection+json"}
      response = dao.getURL(url, headers)
      status = response.status
      logger.debug("{} ==status==> {}".format(url, status))
  
      if status != 200:
          message = str(response.data)
  
          if status == 404:
              # the URL not exists on the specific domain
              return None
  
          if status == 400:
              if "Term is out of range" in message:
                  raise TermEvalNotCreated(url, status, message)
  
          raise DataFailureException(url, status, message)
  
      return json.loads(response.data)