Error 5007: An actionscript definition must have at least on externally

Hello everybody i got a bit of a problem.

When i test my “game” i get this error and i really don’t know how to get rid of it.

The error is 5007: An ActionScript file must have at least one externally visible definition.

And it supposed to caused bij the first line of the code ( says the error compiler)

Here is my code

package {
import flash.display.*;

public class MatchingGame1 extends MovieClip {
public function MatchingGame1():void {
for(var x:uint=0;x<6;x++) {
for(var y:uint=0;y<6;y++) {
var thisCard:Card = new Card();
thisCard.stop();
thisCard.x = x52+120;
thisCard.y = y
52+45;
addChild(thisCard);
}
}
}

}
}

Greets michiel