code: func (s virtualDiskSubresourceSorter) Less(i, j int) bool {
  	mi := s[i].(map[string]interface{})
  	mj := s[j].(map[string]interface{})
  	return mi["unit_number"].(int) < mj["unit_number"].(int)
  }
docs: // Less helps implement sort.Interface for virtualDiskSubresourceSorter.