code: func (c *cinderPlugin) VolumeDelete(pv *v1.PersistentVolume) error {
  	if pv == nil || pv.Spec.Cinder == nil {
  		return fmt.Errorf("invalid Cinder PV: %v", pv)
  	}
  	volumeID := pv.Spec.Cinder.VolumeID
  	err := c.cloud.DeleteVolume(volumeID)
  	if err != nil {
  		return err
  	}
  
  	return nil
  }
docs: // VolumeDelete deletes the specified volume passed on pv