python 实例属性之单，双下划线

             1
            class
             A:

             2
            def
            __init__(self,name=‘Andy‘):
 3         self._name = name 
 4 5class B:
 6def__init__(self,name = ‘Jack‘,age=19):
 7         self.__name = name  # 私有属性(变量)，只有类对象自己能访问，子类也不能访问 8         self._age = age     # 保护变量，类，及子类对象可以访问 910class C(B):
11def h(self):
12print(‘hello‘)
1314 a = A()
15 b = B()
16 c = C()
17print(a._name)  # 输出Adny18print(b._B__name)   # 私有属性在类外的访问方式：对象._类__属性名19print(c._age)   # 输出1920print(c._C__name)   # AttributeError: ‘C‘ object has no attribute ‘_C__name‘子类不能访问