python注解（装饰器）的用法

带参数的要用三层def，第一层写注解里的参数，第二层写函数，第三层写具体逻辑。

如果是不带参数的注解，直接使用后两层即可

def needPermission(permissionstr):
    def decorator(func):
        def hasPermission(self,*args, **kw):
            sessionid = self.get_cookie("session_id")
            verification = self.get_cookie("verification")
            # print(sessionid)
            # print(verification)
            islogin, content = AuthSdk().isLogin(sessionid, verification)
            permissionList = []
            if islogin:
                permissionList = content["permissions"]
            else:
                self.set_status(401)
                self.write(R().errorCodeMsg(401, "认证不通过，请确认是否登录"))
                return
            # print('%s %s %s():' % (self, permissionstr, func.__name__))
            if permissionstr not in permissionList:
                self.set_status(403)
                self.write(R().errorCodeMsg(403, "没有访问权限"))
                return
            else:
                return func(self, *args, **kw)
        return hasPermission
    return decorator