Import Tween Class once or multiple times?

Hello everyone. I am using the tween class on my first key frame of my mc. It looks like this;

import mx.transitions.Tween;
import mx.transitions.easing.*;
var myTween:Tween = new Tween(main_mc, "_x", mx.transitions.easing.Elastic.easeOut,590, 0, 3, true);

However my question is if I have multiple mcs that will use the same code how do i reference it? Currently I have the above code duplicated on two key frames, one of the first and another after a stop keyframe.

I am thinking I should put this in a global function or maybe some other way but not sure how. Any help is appreciated.