python 自定义的异常类

class InputException(Exception):
    '''自定义的异常类'''
    def __init__(self,length,atleast):
        self.length = length
        self.atleast = atleast
 
def test_except():
    try:
        s = input("请输入:")
        if len(s) < 4:
            # raise引发一个自己定义的异常
            raise InputException(len(s),3)
    except InputException as e:
        print("InputException：输入的长度是%d，长度至少应是%d"%(e.length,e.atleast))
    
    else:
        print("输入数值为:{}".format(s))

test_except()