code: def check_correct_host(self):
          
          if self._host == 'knoema.com':
              return
          url = self._get_url('/api/1.0/frontend/tags')
          req = urllib.request.Request(url)
          try:
              resp = urllib.request.urlopen(req)
          except:
              raise ValueError('The specified host {} does not exist'.format(self._host))
docs: The method checks whether the host is correctly set and whether it can configure the connection to this host. Does not check the base host knoema.com