Manipulate user groups

I see that the API Client internal folder contains a usergroup package, which could do this, but the RESTClient doesn't.

https://pkg.go.dev/github.com/mittwald/goharbor-client/v5@v5.0.3/apiv2/internal/api/client/usergroup
https://github.com/mittwald/goharbor-client/tree/v5.0.3/apiv2

Is it possible somehow to manipulate (eg.: delete) groups using this package?