您如何重构此条件以使用多态？

# 定义一个接口，即一个包含共享方法的基类
class Shape:
    def area(self):
        pass

# 实现接口的子类
class Circle(Shape):
    def __init__(self, radius):
        self.radius = radius

    def area(self):
        return 3.14159 * self.radius ** 2

class Rectangle(Shape):
    def __init__(self, width, height):
        self.width = width
        self.height = height

    def area(self):
        return self.width * self.height

# 使用多态
def print_area(shape):
    print(shape.area())

circle = Circle(5)
rectangle = Rectangle(4, 6)

print_area(circle)
print_area(rectangle)