code: func RequireOK(resp *http.Response, err error) (*http.Response, error) {
  	if err != nil {
  		return nil, err
  	}
  	if resp.StatusCode != http.StatusOK {
  		return nil, extractError(resp)
  	}
  	return resp, nil
  }
docs: // RequireOK is used to verify response status code is a successful one (200 OK)