python自定义异常类

# 自定义异常类，集成Exception
class ShortInputError(Exception):
    def __init__(self, length, min_len):
        self.length = length
        self.min_len = min_len

    # 设置抛出异常的描述信息
    def __str__(self):
        return f'你输入的长度是{self.length},不能少于{self.min_len}个字符。'


def main():
    flag = True
    while flag == True:
        try:
            con = input('请输入密码：')
            if len(con) < 3:
                raise ShortInputError(len(con), 3)
        except Exception as result:
            print(result)
        else:
            print('密码已经输入完成！')
            flag == False
            break


main()