类的继承之新增、定制

class Student:
    # 初始化函数，为每个实例创建4个参数（其中后3个参数有默认值）
    def __init__(self, name, job=None, time=0.00, time_effective=0.00): 
        self.name = name
        self.job = job
        self.time = time
        self.time_effective = time_effective

    def count_time(self, hour, rate):
        self.time += hour
        self.time_effective += hour * rate  # 有效时间=投入时间×学习效率

class Aaa(Student):# 创建子类继承
    # 修改初始化方法，注意：job进行赋值为字符串’programmer‘
    def __init__(self,name,job='programmer',time=0.00,time_effective=0.00):
        self.name = name
        self.job = job
        self.time = time
        self.time_effective = time_effective
    # 修改父类方法，rate=1
    def count_time(self,hour,rate=1):
        self.time += hour
        self.time_effective += hour * rate  # 有效时间=投入时间×学习效率

student1 = Student('韩梅梅')
print(student1.job)
student1.count_time(10, 0.8)  # 学习效率为0.8
print(student1.time_effective)

student2 = Aaa('张三')# 子类的实例化
print(student2.job)
student2.count_time(10)
print(student2.time_effective)