class CommandError(Exception):
    
    def __init__(self, message: str = None):
        self.message = message
    
    def __str__(self):
        return self.message


class CommandNotFoundError(CommandError):
    
    def __init__(self, message: str = None):
        super().__init__("未知命令: "+message)


class CommandPrivilegeError(CommandError):
    
    def __init__(self, message: str = None):
        super().__init__("权限不足: "+message)


class ParamNotEnoughError(CommandError):
    
    def __init__(self, message: str = None):
        super().__init__("参数不足: "+message)


class CommandOperationError(CommandError):
    
    def __init__(self, message: str = None):
        super().__init__("操作失败: "+message)