An example to show how an obtained access and refresh token can be stored persistently and re-used across application restarts. This results in fewer requests to spotifys authentication endpoints and a faster experience for the user. The example uses [PKCE](pkce.md) in combination with the `PKCEAuthenticator`, which automatically refreshes expired tokens.
The access and refresh token is saved in a `credentials.json` file of the current working directory.
Before running it, make sure you created an app in your [spotify dashboard](https://developer.spotify.com/dashboard/) and `https://localhost:5543` is a redirect uri of it.