code: func (r *Root) Get(name string) (volume.Volume, error) {
  	r.m.Lock()
  	v, exists := r.volumes[name]
  	r.m.Unlock()
  	if !exists {
  		return nil, ErrNotFound
  	}
  	return v, nil
  }
docs: // Get looks up the volume for the given name and returns it if found