Creating a Group at project level - GraphGroupCreationContext issue

Just want to verify if this API is ready to be consumed and used or this particular one is still at preview?

Looks like the request body and the model doesn't have the same attributes:
In here, there's a displayName and description:
https://docs.microsoft.com/en-us/rest/api/azure/devops/graph/groups/create?view=azure-devops-rest-5.0#create_a_group_at_the_project_level

But on the client, where it asks for a graphgroupcreationcontext, it only asks for a storagekey. And the warning here states that we shouldn't use this for creation of a group:
https://docs.microsoft.com/en-us/rest/api/azure/devops/graph/groups/create?view=azure-devops-rest-5.0#graphgroupcreationcontext

How can I create a group in a project level given the api above?

Beginne mit dem Clientmodell GraphGroupCreationContext und vergleiche es mit der verknüpften Azure DevOps REST-Dokumentation zur Erstellung von Gruppen auf Projektebene. Ermittle, ob das Modell und die dokumentierten Anfrageattribute übereinstimmen, und bestätige die unterstützte Methode zum Erstellen einer Gruppe auf Projektebene.