code: def get_portal_url_base(self):
          
          api_url = urlparse(self.url).hostname
          portal_url = re.sub('^api\.', '', api_url)
          portal_url = re.sub(r'api', '', portal_url)
          return portal_url
docs: Determine root url of the data service from the url specified.
          :return: str root url of the data service (eg: https://dataservice.duke.edu)