写一段面向对象的python代码

class Person: def init(self, name, age): self.name = name self.age = age

def say_hello(self):
    print(f"Hello, my name is {self.name} and I am {self.age} years old.")

class Student(Person): def init(self, name, age, grade): super().init(name, age) self.grade = grade

def say_hello(self):
    super().say_hello()
    print(f"I am a student in grade {self.grade}.")

class Teacher(Person): def init(self, name, age, subject): super().init(name, age) self.subject = subject

def say_hello(self):
    super().say_hello()
    print(f"I am a teacher of {self.subject}.")

person1 = Person("John", 25) person1.say_hello()

student1 = Student("Jane", 16, 11) student1.say_hello()

teacher1 = Teacher("Mr. Smith", 40, "math") teacher1.say_hello(