python import nacl.utils private_key = nacl.utils.random(nacl.secret.SecretBox.KEY_SIZE) public_key = nacl.public.PrivateKey(private_key).public_key alice_key_agreement = private_key.public_key bob_key_agreement = public_key alice_shared_key = alice_key_agreement.shared_key(bob_key_agreement) bob_shared_key = bob_key_agreement.shared_key(alice_key_agreement)