"this" to .as

if i have the following actionscript on frame1 inside a movieclip with the identifier name “inventory”

var container_mc:MovieClip = this.createEmptyMovieClip("container_mc", this.getNextHighestDepth());

and i want to use it in an external .as file instead. what would i change “this” to? i tried using _root.createEmptyMovieClip and _root.inventory.createEmptyMovieClip. i get no errors but i also do not get the text to show up in the code that follows. ( it DOES show up if i leave it embedded in the movie clip instead of putting it into the .as file )