code: func (m *Manager) NewVolumeFromProvider(providerID string, info *volume.Info) (volume.Volume, error) {
  	m.mutex.Lock()
  	defer m.mutex.Unlock()
  	if p, ok := m.providers[providerID]; ok {
  		return managerProviderProxy{p, m}.NewVolume(info)
  	}
  	return nil, ErrNoSuchProvider
  }
docs: /*
  	volume.Manager implements the volume.Provider interface by
  	delegating NewVolume requests to the named Provider.
  */