'Creates a group_snapshot.'

@infinisdk_to_cinder_exceptions
def create_group_snapshot(self, context, group_snapshot, snapshots):

    if (not vol_utils.is_group_a_cg_snapshot_type(group_snapshot)):
        raise NotImplementedError()
    infinidat_cg = self._get_infinidat_cg(group_snapshot.group)
    group_snap_name = self._make_group_snapshot_name(group_snapshot)
    new_group = infinidat_cg.create_snapshot(name=group_snap_name)
    for infinidat_snapshot in new_group.get_members():
        parent_name = infinidat_snapshot.get_parent().get_name()
        for cinder_snapshot in snapshots:
            if (cinder_snapshot.volume_id in parent_name):
                snapshot_name = self._make_snapshot_name(cinder_snapshot)
                infinidat_snapshot.update_name(snapshot_name)
    return (None, None)
