'Delete a volume group snapshot.
:param context: the context
:param group_snapshot: the volume group snapshot to be deleted
:param snapshots: the snapshot objects
:returns: model_update, snapshots_model_update'

def delete_group_snapshot(self, context, group_snapshot, snapshots):

    (model_update, snapshots_model_update) = self._delete_group_snapshot(group_snapshot, snapshots)
    return (model_update, snapshots_model_update)
