All that example does is get retrieve a collection and then has some post-response code that creates a visualization that you can copy and paste. (It uses sendRequest to hit another API for the conversion).
If you are getting a forbidden error, its because of the authorization on the request. What status code are you getting? A 401?
Hi @michaelderekjones , thank for your patience i had very busy days.
By the way i tried to set the X-API-Key in the collection like you suggest and i set also the value of {{postman_api_key}} in the Variables tab
then i create a GET request inside the collection in the pic with the API Key e the id of the collection that i want the swagger in output but i receive the same response like the foloowing pic: