class Student(): 
    def __init__(self, name, age, grade): 
        self.name = name 
        self.age = age 
        self.grade = grade
在以下类定义中添加一个功能。
class Student(): 
    def __init__(self, name, age, grade, gender): 
        self.name = name 
        self.age = age 
        self.grade = grade
        self.gender = gender