code: def area(self):
          
          # area of the sides of the extrusion
          area = abs(self.primitive.height *
                     self.primitive.polygon.length)
          # area of the two caps of the extrusion
          area += self.primitive.polygon.area * 2
          return area
docs: The surface area of the primitive extrusion.
  
          Calculated from polygon and height to avoid mesh creation.
  
          Returns
          ----------
          area: float, surface area of 3D extrusion