Hard times with packages

1

i have not had to hard of a time getting used to the new syntax of AS3, however i cannot figure out packages, i sniped this enter frame script that is defined in a package, but when ever i publish it it gives an error report

THE CODE
package {
import flash.display.;
import flash.events.;

public class TestEnterFrame extends Sprite {
    public function TestEnterFrame() {
        addEventListener(Event.ENTER_FRAME, onEnterFrame);
    }

    private function onEnterFrame(ev:Event):void {
        trace("onenterframe:"+ev);
    }
}

}

THE ERROR
1037: Packages cannot be nested.