Fix import ordering in interfaces
diff --git a/src/cryptography/hazmat/primitives/interfaces/__init__.py b/src/cryptography/hazmat/primitives/interfaces/__init__.py
index 2f9880d..b025d15 100644
--- a/src/cryptography/hazmat/primitives/interfaces/__init__.py
+++ b/src/cryptography/hazmat/primitives/interfaces/__init__.py
@@ -4,10 +4,10 @@
 
 from __future__ import absolute_import, division, print_function
 
-import six
-
 import abc
 
+import six
+
 from cryptography.hazmat.primitives.interfaces.ciphers import (
     BlockCipherAlgorithm,
     CipherAlgorithm,