code: func (k Key) String() string {
  	fp := ""
  	if len(k.Fingerprint) > 24 {
  		fp = k.Fingerprint[24:]
  	}
  	out := fmt.Sprintf("%s   %dD/0x%s %s", k.KeyType, k.KeyLength, fp, k.CreationDate.Format("2006-01-02"))
  	if !k.ExpirationDate.IsZero() {
  		out += fmt.Sprintf(" [expires: %s]", k.ExpirationDate.Format("2006-01-02"))
  	}
  	out += "\n      Key fingerprint = " + k.Fingerprint
  	for _, id := range k.Identities {
  		out += fmt.Sprintf("\n" + id.String())
  	}
  	return out
  }
docs: // String implement fmt.Stringer. This method produces output that is close to, but
  // not exactly the same, as the output form GPG itself