code: func isAttachmentName(unknownString string) bool {
  	// 68 == "csi-" + len(sha256hash)
  	if strings.HasPrefix(unknownString, "csi-") && len(unknownString) == 68 {
  		return true
  	}
  	return false
  }
docs: // isAttachmentName returns true if the string given is of the form of an Attach ID
  // and false otherwise