(self, user_number, password, user_info=None)
user_info可能是email, 也可能user_name, 具体取决于group的protocol
user_info可能是email, 也可能user_name, 具体取决于group的protocol
user_info可能是email 也可能user_name 具体取决于group的protocol
def __init__(self, user_number, password, user_info=None):
        """
        user_info可能是email, 也可能user_name, 具体取决于group的protocol
        """
        self.__password = password
        self.user_info = user_info
        self.user_number = user_number
def __init__ ( self , user_number , password , user_info = None ) : self . __password = password self . user_info = user_info self . user_number = user_number