code: public function register(Container $pimple)
      {
          $pimple['staff'] = function ($pimple) {
              return new Staff($pimple['access_token']);
          };
  
          $pimple['staff_session'] = $pimple['staff.session'] = function ($pimple) {
              return new Session($pimple['access_token']);
          };
      }
docs: Registers services on the given container.
  
  This method should only be used to configure services and parameters.
  It should not get services.
  
  @param Container $pimple A container instance