code: func (h *Host) ObjectFromRef(permanodeRef blob.Ref) (*Object, error) {
  	ctx := context.TODO()
  	res, err := h.search.Describe(ctx, &search.DescribeRequest{
  		BlobRef: permanodeRef,
  		Depth:   1,
  	})
  	if err != nil {
  		return nil, err
  	}
  	db, ok := res.Meta[permanodeRef.String()]
  	if !ok {
  		return nil, fmt.Errorf("permanode %v wasn't in Describe response", permanodeRef)
  	}
  	if db.Permanode == nil {
  		return nil, fmt.Errorf("permanode %v had no DescribedPermanode in Describe response", permanodeRef)
  	}
  	return &Object{
  		h:       h,
  		pn:      permanodeRef,
  		attr:    map[string][]string(db.Permanode.Attr),
  		modtime: db.Permanode.ModTime,
  	}, nil
  }
docs: // ObjectFromRef returns the object given by the named permanode