code: func SaveChartfile(filename string, cf *chart.Metadata) error {
  	out, err := yaml.Marshal(cf)
  	if err != nil {
  		return err
  	}
  	return ioutil.WriteFile(filename, out, 0644)
  }
docs: // SaveChartfile saves the given metadata as a Chart.yaml file at the given path.
  //
  // 'filename' should be the complete path and filename ('foo/Chart.yaml')