Cache tutorial help!

Can someone explaien how i should use those two lines of code?

I have one main.swf and one pic.swf. pic.swf is loaded from the maintimeline in main.swf with the command

loadMovie(“pic.swf”, “pic1”);

and i wnat to use the unique identifier but i dont know where to enter the code from…

http://www.kirupa.com/developer/actionscript/tricks/cache.htm

any help would be great !:toad: