﻿class Person:

    def display_person(self):
        print("Person Class")

class Student(Person):

    def display_student(self):
        print("Student Class")

class GraduateStudent(Student):

    def display_graduate_student(self):
        print("Graduate Student Class")

student = GraduateStudent()

student.display_person()
student.display_student()
student.display_graduate_student()