Creation of dynamic property DEPRECATED

This works for me in the BaseController.

PHP Code:

use Config\Services;

/**
 * E.g.: $this->session = \Config\Services::session();
 * Ensure that the session is started and running
 */
if (session_status() == PHP_SESSION_NONE) {
    $this->session = Services::session();
} 


But you still explicitly declare $session as a property?