代码问题！

class Person(object):
    def __init__(self,a):
        self.a=a
class Student(Person):
    def __init__(self,a):
        super(Student,self).__init__(a )
class Teacher(Person):
    def __init__(self,a):
        super(Teacher ,self).__init__(a )
class SkillMixin(object):
    def __init__(self,skill):
        self.skill=skill
class BasketballMixin(SkillMixin ):
    def skill(self):
        return 'basketball'
class FootballMixin(SkillMixin):
    def skill(self):
        return 'football'
class BStudent(Student ,BasketballMixin ):
    def __init__(self,a,skill):
        super(BStudent,self).__init__(a)
        super(BasketballMixin ,self).__init__(skill)
class FTeacher(Teacher ,FootballMixin ):
    def __init__(self,a,skill):
        super(FTeacher,self).__init__(a)
        super(FootballMixin ,self).__init__(skill)
b=BStudent ('Tom','basketball')
print b.skill
f=FTeacher ('Bob','football')
print f.skill