Fix up README example

Author: decentral1se

README.md

@@ -13,10 +13,18 @@ $ pip install hypercore-crypto
 ## Example
 
 ```python
-from hypercore_crypto import data, key_pair
 from pysodium import crypto_sign_PUBLICKEYBYTES
 
+from hypercore_crypto import data, key_pair
+
 public_key, secret_key = key_pair()
 assert len(public_key) == crypto_sign_PUBLICKEYBYTES
+
 print(data(b"hello world").hex())
 ```
+
+Output:
+
+```sh
+ccfa4259ee7c41e411e5770973a49c5ceffb5272d6a37f2c6f2dac2190f7e2b7
+```