private static SecretBytes getPrivateP384Value() {
    return SecretBytes.copyFrom(
        Hex.decode(
            "670dc60402d8a4fe52f4e552d2b71f0f81bcf195d8a71a6c7d84efb4f0e4b4a5d0f60a27c9"
                + "4caac46bdeeb79897a3ed9"),
        InsecureSecretKeyAccess.get());
  }
Test vectors for HPKE. Generated by hand from the implementation here.
java_src/src/main/java/com/google/crypto/tink/hybrid/internal/testing/HpkeTestUtil.java