code: def poll(self, url, initial_delay=2, delay=1, tries=20, errors=STRICT, is_complete_callback=None, **params):
          
          time.sleep(initial_delay)
          poll_response = None
  
          if is_complete_callback == None:
              is_complete_callback = self._default_poll_callback
  
          for n in range(tries):
              poll_response = self.make_request(url, headers=self._headers(),
                                                errors=errors, **params)
  
              if is_complete_callback(poll_response):
                  return poll_response
              else:
                  time.sleep(delay)
  
          if STRICT == errors:
              raise ExceededRetries(
                  "Failed to poll within {0} tries.".format(tries))
          else:
              return poll_response
docs: Poll the URL
          :param url - URL to poll, should be returned by 'create_session' call
          :param initial_delay - specifies how many seconds to wait before the first poll
          :param delay - specifies how many seconds to wait between the polls
          :param tries - number of polls to perform
          :param errors - errors handling mode, see corresponding parameter in 'make_request' method
          :param params - additional query params for each poll request