@dataclass(frozen=True)
class KeyPair:
    private_key: Ed25519PrivateKey
    public_key: Ed25519PublicKey

    @classmethod
    def generate(cls) -> KeyPair:
        private_key = Ed25519PrivateKey.generate()
        return cls(private_key=private_key, public_key=private_key.public_key())

    def public_hex(self) -> str:
        raw = self.public_key.public_bytes(
            encoding=serialization.Encoding.Raw,
            format=serialization.PublicFormat.Raw,
        )
        return raw.hex()