code: func (k *KeyringMemberRevocationType) UnmarshalText(b []byte) error {
  	switch string(b) {
  	case "org_removal":
  		*k = OrgRemovalRevocationType
  	case "key_revocation":
  		*k = KeyRevocationRevocationType
  	case "machine_destroy":
  		*k = MachineDestroyRevocationType
  	case "machine_token_destroy":
  		*k = MachineTokenDestroyRevocationType
  	default:
  		return errBadRevocationType
  	}
  
  	return nil
  }
docs: // UnmarshalText implements the encoding.TextUnmarshaler interface, used for
  // JSON unmarshaling.