code: func (c *cinderPlugin) SnapshotDelete(src *crdv1.VolumeSnapshotDataSource, _ *v1.PersistentVolume) error {
  	if src == nil || src.CinderSnapshot == nil {
  		return fmt.Errorf("invalid VolumeSnapshotDataSource: %v", src)
  	}
  	snapshotID := src.CinderSnapshot.SnapshotID
  	err := c.cloud.DeleteSnapshot(snapshotID)
  	if err != nil {
  		return err
  	}
  	return nil
  }
docs: // SnapshotDelete deletes a VolumeSnapshot
  // PersistentVolume is provided for volume types, if any, that need PV Spec to delete snapshot