If Plato argued that there are perfect geometric shapes that exist outside the material?

and nature only produces crude facsimiles of this removed perfection, then did he also believe that there are perfect ideals of imperfect geometric shapes? I mean, imagine you draw square but you are poor artist so the lines dont even join up: So is there a perfect version of your retarded square outside the material also? please explain?.. I want to know if this same logic can be used for perfect ideals of literature. (eg, is Hamlet the perfect tragedy?)