'create a snapshot from volume'

def create_snapshot(self, snapshot):

    snapshot_name = self._translate_volume_name(snapshot['name'])
    volume_name = self._translate_volume_name(snapshot['volume_name'])
    volume_size = snapshot['volume_size']
    self._create_snapshot(snapshot_name, volume_name, volume_size, zte_pub.ZTE_SNAPSHOT_MODE_RW)
