def METHOD_NAME(self):
    """Test whether the message is encrypted using public/private keys."""
    # get public and private keys
    private_key = rsa.generate_private_key(public_exponent=65537, key_size=4096, backend=default_backend())
    public_key = private_key.public_key()
    pubkey = public_key.public_bytes(
        encoding=serialization.Encoding.PEM,
        format=serialization.PublicFormat.SubjectPublicKeyInfo,
    )
    # encryption
    test_message = "this is a test message"
    encrypted_key, encrypted_message = asymmetric_encrypt(pubkey.decode(), test_message)
    self.assertNotEqual(test_message, encrypted_message)
    # decryption
    decrypted_key = private_key.decrypt(
        b64decode(encrypted_key.encode()),
        padding.OAEP(mgf=padding.MGF1(algorithm=hashes.SHA256()), algorithm=hashes.SHA256(), label=None),
    )
    fernet = Fernet(decrypted_key)
    decrypted_message = fernet.decrypt(encrypted_message.encode()).decode()
    self.assertEqual(decrypted_message, test_message)