pythonクラスの継承と再ロード

>>> class human:
    __age=0
    __sex=''
    __height=0
    __weight=0
    name=''
    def __init__(self,age,sex,height,weight):
        self.__age=age
        self.__sex=sex
        self.__height=height
        self.__weight=weight
    def setname(self,name):
        self.name=name
    def show(self):
        print(self.name)
        print(self.__age)
        print(self.__sex)
        print(self.__height)
        print(self.__weight)


>>> class student(human):#    human   student 
    __classes=0
    __grade=0
    __num=0
    def __init__(self,classes,grade,num,age,sex,height,weight):#  
        self.__classes=classes
        self.__grade=grade
        self.__num=num
        human.__init__(self,age,sex,height,weight)#  human  __init__  ，   huamn    ，  huamn          ，  “  .   ”     
    def show(self):#  show()  
        human.show(self)#  huamnn  show  
        print(self.__classes)
        print(self.__grade)
        print(self.__num)
>>> a=student(12,3,20070305,19,'male',175,65)#     a  
>>> a.setname('tom')#  setname  
>>> a.show()#  show  ，      show      
tom
19
male
175
65
12
3
20070305