'Creates a snapshot.'

def create_snapshot(self, lun_id, snap_name, keep_for=None):

    lun = self.get_lun(lun_id=lun_id)
    try:
        lun.create_snap(snap_name, allow_rw=True, auto_delete=False, keep_for=keep_for)
    except storops_ex.VNXSnapNameInUseError as ex:
        LOG.warning('Snapshot    %(name)s    already    exists.    Message:    %(msg)s', {'name': snap_name, 'msg': ex.message})
