What do I do with the lmc_tween.as file

I am trying to learn how to script tweening and my tutorial says I need this Imc_tween.as file, which I was able to download. But I dont know what I am supposed to do with it, Do I place it somewhere or link it to my file???

here is a link to the tutorial I am trying to complete:
http://www.free-webmaster-resource.com/tutorials/flash/basics/tutorial001/index.php?tutorial_id=460&tPage=1

thanks