code: func (s *OauthService) AuthorizeURL(clientID string, options *AuthorizationOptions) string {
  	uri, _ := url.Parse(strings.Replace(s.client.BaseURL, "api.", "", 1))
  	uri.Path = "/oauth/authorize"
  	query := uri.Query()
  	query.Add("client_id", clientID)
  	query.Add("response_type", "code")
  	uri.RawQuery = query.Encode()
  
  	path, _ := addURLQueryOptions(uri.String(), options)
  	return path
  }
docs: // AuthorizeURL generates the URL to authorize an user for an application via the OAuth2 flow.