python继承是如何实现的

class SubClassName(ParentClass1 [, ParentClass2, ...]):

    class_suite

class Parent(object):

    '''

    parent class

    '''

    numList = []

    def numdiff(self, a, b):

        return a-b

class Child(Parent):

    pass

c = Child()   

# subclass will inherit attributes from parent class

#子类继承父类的属性  

Child.numList.extend(range(10))

print(Child.numList)

print("77 - 2 =", c.numdiff(77, 2))

# built-in function issubclass()

print(issubclass(Child, Parent))

print(issubclass(Child, object))

# __bases__ can show all the parent classes

#bases属性查看父类

print('the bases are:',Child.__bases__)

# doc string will not be inherited

#doc属性不会被继承

print(Parent.__doc__)

print(Child.__doc__)