python中数据模型，以下两种声明方式有什么区别

class SearpcClient(object):

    def call_remote_func_sync(self, fcall_str):
        raise NotImplementedError()
        
        
class RpcClientBase(SearpcClient):
    
    def __init__(self, ccnet_client_pool, service_name, retry_num=1,
                 is_remote=False, remote_peer_id='', req_pool=False):
        SearpcClient.__init__(self)
        self.pool = ccnet_client_pool
        self.service_name = service_name
        self.retry_num = retry_num
        self.is_remote = is_remote
        self.remote_peer_id = remote_peer_id
        self.req_pool = req_pool
        if self.is_remote and len(self.remote_peer_id) != 40:
            raise ValueError("Invalid remote peer id")
            
            
class User(object):
    is_staff = False
    is_active = False
    is_superuser = False
    groups = []
    org = None
    objects = UserManager()