1 #!/usr/bin/python3
 12 class Person(object):
 13     pass
 14 class Student(Person):
 15     pass
 16 class Teacher(Person):
 17     pass
 18 class SkillMixin(object):
 19     pass
 20 class BasketballMixin(SkillMixin):
 21     def skill(self):
 22         return 'basketball'
 23 class FootballMixin(SkillMixin):
 24     def skill(self):
 25         return 'Football'
 26 class BStudent(BasketballMixin,Student,):
 27     pass
 28 class FTeacher(FootballMixin,Teacher):
 29     pass
 30 
 31 s=BStudent()
 32 print(s.skill())
 33 t=FTeacher
 34 print(t.skill())

TypeError: skill() missing 1 required positional argument: 'self'