code: func (s *UsersService) LookupIyoID(identifier string, headers, queryParams map[string]interface{}) (IyoID, *http.Response, error) {
  	var err error
  	var respBody200 IyoID
  
  	resp, err := s.client.doReqNoBody("GET", s.client.BaseURI+"/users/identifiers/"+identifier, headers, queryParams)
  	if err != nil {
  		return respBody200, nil, err
  	}
  	defer resp.Body.Close()
  
  	switch resp.StatusCode {
  	case 200:
  		err = json.NewDecoder(resp.Body).Decode(&respBody200)
  	default:
  		err = goraml.NewAPIError(resp, nil)
  	}
  
  	return respBody200, resp, err
  }
docs: // Lookup the username for an iyo id