code: func (p *nfsProvisioner) createExport(directory string, rootSquash bool) (string, uint16, error) {
  	path := path.Join(p.exportDir, directory)
  
  	block, exportID, err := p.exporter.AddExportBlock(path, rootSquash, p.exportSubnet)
  	if err != nil {
  		return "", 0, fmt.Errorf("error adding export block for path %s: %v", path, err)
  	}
  
  	err = p.exporter.Export(path)
  	if err != nil {
  		p.exporter.RemoveExportBlock(block, exportID)
  		return "", 0, fmt.Errorf("error exporting export block %s: %v", block, err)
  	}
  
  	return block, exportID, nil
  }
docs: // createExport creates the export by adding a block to the appropriate config
  // file and exporting it