code: func RetrieveGPGKey(pgpKey string) (string, error) {
  	const keybasePrefix = "keybase:"
  
  	encryptionKey := pgpKey
  	if strings.HasPrefix(pgpKey, keybasePrefix) {
  		publicKeys, err := pgpkeys.FetchKeybasePubkeys([]string{pgpKey})
  		if err != nil {
  			return "", errwrap.Wrapf(fmt.Sprintf("Error retrieving Public Key for %s: {{err}}", pgpKey), err)
  		}
  		encryptionKey = publicKeys[pgpKey]
  	}
  
  	return encryptionKey, nil
  }
docs: // RetrieveGPGKey returns the PGP key specified as the pgpKey parameter, or queries
  // the public key from the keybase service if the parameter is a keybase username
  // prefixed with the phrase "keybase:"