当一个类中有多个__init__方法时，执行代码会报错；也就是说一个类中采用__init__方法来实现定义多个构造器时不可取的

class My_Date():

    def __init__(self,year,month,day):
        #指定的年月日
        self.year=year
        self.month=month
        self.day=day

    def __init__(self,year,month):
        self.year = year
        self.month = month


if __name__ == '__main__':
    d=My_Date(2022,8,2)
    print(d)

报错：TypeError: init() takes 3 positional arguments but 4 were given

解决方法：采用类方法或者静态方法定义多个构造器

from datetime import datetime,timedelta
class My_Date1:
    def __init__(self,year,month,day):
        self.year=year
        self.month=month
        self.day=day

    def run(self):
        return 'working'

    @classmethod
    def today(cls):
        now_time=datetime.now()
        return cls(now_time.year,now_time.month,now_time.day)


if __name__ == '__main__':
    my_date=My_Date1(2022,12,12)
    print(my_date)
    print(my_date.run())

    t=My_Date1.today()
    print(t)
    print(t.year)
    print(t.day)
    print(t.run())

执行结果：
<main.My_Date1 object at 0x0000026C0986ED00>
working
<main.My_Date1 object at 0x0000026C0986ECA0>
2022
3
working