Flask多对多表关联后引用失败问题

# 权限类
class CMSPersmission(object):
    #255的二进制方式来表示 1111 1111
    ALL_PERMISSION = 0b11111111
    #1 访问者权限
    VISITOR =        0b00000001
    #2 管理帖子的权限
    POSTER =         0b00000010
    # 3 管理评论的权限
    COMMENTER =      0b00000100
    # 4 管理板块的权限
    BOARDER =        0b00001000
    # 5 管理前台用户的权限
    FRONTUSER =      0b00010000
    # 6 管理后台用户的权限
    CMSUSER =        0b00100000
    # 7 管理后台管理员的权限
    ADMINER =        0b01000000

class CMSRole(db.Model):
    __tablename__ = 'cms_role'
    id = db.Column(db.Integer, primary_key=True, autoincrement=True)
    name = db.Column(db.String(50), nullable=False)
    desc = db.Column(db.String(200),nullable=True)
    create_time = db.Column(db.DateTime,default=datetime.now)
    permissions = db.Column(db.Integer,default=CMSPersmission.VISITOR)

    users = db.relationship('CMSUser',secondary=cms_role_user,backref='roles')

class CMSUser(db.Model):
    __tablename__ = "cms_user"
    id = db.Column(db.Integer,primary_key=True,autoincrement=True)
    username = db.Column(db.String(50),nullable=False)
    _password = db.Column(db.String(100),nullable=False)
    email = db.Column(db.String(50),nullable=False,unique=True)
    join_time  = db.Column(db.DateTime,default=datetime.now)

    def __init__(self,username,password,email):
        self.username = username
        self.password = password
        self.email = email

    # 对password进行保护，使用password名字使用_password
    @property
    def password(self):
        return self._password
    # 重定义设置方法
    @password.setter
    def password(self,raw_password):
        self._password = generate_password_hash(raw_password)

    def check_password(self,raw_password):
        result = check_password_hash(self.password,raw_password)
        return result

    @property
    def permissions(self):
        if not self.roles:
            return 0
        all_permissions = 0
        for role in self.roles:
            permissions = role.permissions
            all_permissions |= permissions
        return all_permissions

    def has_permission(self,permission):
        # 外键的属性引用，解决undefined问题
        all_permissions = CMSPersmission.ALL_PERMISSION
        result = all_permissions&permission == permission
        return result
        # return self.permissions & permission == permission

    @property
    def is_developer(self):
        return self.has_permission(CMSPersmission.ALL_PERMISSION)

# 映射
cms_role_user = db.Table(
    "cms_role_user",
    db.Column("cms_role_id",db.Integer,db.ForeignKey("cms_role.id"),primary_key=True),
    db.Column("cms_user_id",db.Integer,db.ForeignKey("cms_user.id"),primary_key=True)
)

问题描述：

 问题分析：

打开mysql查询表结构：

 打开cms_role_user:

 关联正常，问题出在函数has_permission上：

return self.permissions & permission == permission

问题解决