Unable to load a third_party driver

Hi,

I am trying to add a driver, as in
eg, https://codeigniter.com/user_guide/libra...om-drivers

but instead of adding in ,
  application/libraries/Session/drivers/Session_dummy_driver.php
would like to place/package it under say,
  application/third_party/package1/libraries/Session/drivers/Session_dummy_driver.php

Currently trying in codeigniter-v3.1.11, but unable to load it.

Any help would be appreciated.

Thanks,
V.Krishn