Steps to get this running on py32 and py33 again
diff --git a/tests/primitives/test_block.py b/tests/primitives/test_block.py
index f2da583..8c311d5 100644
--- a/tests/primitives/test_block.py
+++ b/tests/primitives/test_block.py
@@ -13,8 +13,8 @@
     )
     def test_aes_cbc_nopadding(self, key, iv, plaintext, ciphertext):
         cipher = BlockCipher(
-            ciphers.AES(binascii.unhexlify(key)),
-            modes.CBC(binascii.unhexlify(iv), padding.NoPadding())
+            ciphers.AES(binascii.unhexlify(key.encode("ascii"))),
+            modes.CBC(binascii.unhexlify(iv.encode("ascii")), padding.NoPadding())
         )
         actual_ciphertext = cipher.encrypt(binascii.unhexlify(plaintext))
         actual_ciphertext += cipher.finalize()