Create PublicKey XDR object via public key bytes.

        :return: Serialized XDR of PublicKey type.

def account_xdr_object(self):
        """Create PublicKey XDR object via public key bytes.

        :return: Serialized XDR of PublicKey type.
        """
        return Xdr.types.PublicKey(Xdr.const.KEY_TYPE_ED25519,
                                   self.verifying_key.to_bytes())