Provide profile link in user list

Profile link exposed as a user’s (hybrid) property.
On the SEUser there is a method which retrieves a json of data pertaining to the SEUser. Within that json, [there should be a link to the user's profile](http://api.stackexchange.com/docs/types/user). Would it be easier just to create the `profile_link` within the SEUser model as a plain string column?