Python -----issubclass和isinstance

issubclass用于判断一个类是否为另一个类的子类，isinstance用于判断一个对象是否某类的一个实例

import math

class Point:  
    def __init__(self, xValue, yValue):  
        self.X = xValue  
        self.Y = yValue

class Circle(Point):  
    def __init__(self, xValue, yValue, rValue):  
        Point.__init__(self, xValue, yValue)  
        self.Radious = rValue  
  
    def area(self):  
        return math.pi * self.Radious ** 2

print("Point bases:", Point.__bases__)  
print("Circle bases:", Circle.__bases__)  
  
print("Circle is the subclass of Point:", issubclass(Circle, Point))  
print("Point is the subclass of Circle:", issubclass(Point, Circle))


point = Point(3, 4)  
circle = Circle(4, 5, 2) 
print("point is an instace of Point:", isinstance(point, Point))  
print("circle is an instace of Point:", isinstance(circle, Point))