def METHOD_NAME(self) -> str:
    group_name = self._get_param("GroupName")
    description = self._get_param("Description", "")
    group = self.resourcegroups_backend.METHOD_NAME(
        group_name=group_name, description=description
    )
    return json.dumps(
        {
            "Group": {
                "GroupArn": group.arn,
                "Name": group.name,
                "Description": group.description,
            }
        }
    )