'Delete files backing each snapshot in the group snapshot.
:return: An implicit update of snapshot models that the manager will
interpret and subsequently set the model state to deleted.'

@utils.trace_method
def delete_group_snapshot(self, context, group_snapshot, snapshots):

    for snapshot in snapshots:
        self._delete_backing_file_for_snapshot(snapshot)
        LOG.debug('Snapshot    %s    deletion    successful', snapshot['name'])
    return (None, None)
