python 2 和3 区别之一

class classmate:
    def __init__(self,name):
        self.name = name

    def eat(self):
        print ('%s is eating.'%self.name)

    def drink(self):
        print ('%s is drinking'%self.name)

class female(classmate):

    def drink(self):
        print ('%s drink orange juice'%self.name)

class male(classmate):

    def drink(self):
        print ('%s drink alcohol'%self.name)

class pythoner(classmate):

    def occupation(self):
        print ('%s is a pythoner.'%self.name)



class fe_pythoner(pythoner,female):
    pass
class male_pythoner(pythoner,male):
    pass

eva = fe_pythoner('eva')
eva.drink()

sweet = male_pythoner('sweet')
sweet.drink()

对于这段代码若是python2输出为

eva is drinking
sweet is drinking

 

若是python3 输出为

eva drink orange juice
sweet drink alcohol

 

python2 中若要输出出相同的结果要将首行改为class classmate（object）或

 

将

class fe_pythoner(pythoner,female):
pass
class male_pythoner(pythoner,male):
pass
改成

class fe_pythoner(female,pythoner):
pass
class male_pythoner(male,pythoner):
pass

 

 

 

所以写成标准形式class classmate（object）：是一个好习惯。

python2 默认深度优先