AttributeError: 'NoneType' object has no attribute 'permission'
-------------------------------- ----------------------------------`
{% if current_user.can(Permission.MODERATE_COMMENTS) %}

File "/home/centos/Desktop/workspace/flasky_163/app/models.py", line 207, in can def generate_email_change_token(self, new_email, expiration=3600): s = Serializer(current_app.config['SECRET_KEY'], expiration) return s.dumps({'change_email': self.id, 'new_email': new_email}) def can(self, permission): return (self.role.permission & permission) == permission def is_administrator(self): return self.can(Permission.ADMINISTER) def ping(self): AttributeError: 'NoneType' object has no attribute 'permission'`

I have added permission into the database, why does the program still prompt this question? Is there anyone who has completed the flasky project? Please give me some guidance, thank you