Suppose you have to design an application for drawing 2D geometric shapes. Some shapes are complex and may contain one or more shapes, basic or complex. For instance, a House shape includes 3 Rectangle (basic) shapes, a Chimney shape, and an Ellipse (basic) shape. The Chimney is a complex shape and includes 4 Line shapes. A complex shape behaves like a basic shape but also allows one to add/remove basic shapes to/from it. What design pattern must be applied to these shape concepts