diff -r 9623c83ba489 Lib/hmac.py
--- a/Lib/hmac.py	Wed Jun 27 15:26:26 2012 -0400
+++ b/Lib/hmac.py	Sat Jun 30 08:24:03 2012 -0700
@@ -35,7 +35,7 @@
         """
 
         if not isinstance(key, bytes):
-            raise TypeError("expected bytes, but got %r" % type(key).__name__)
+            raise TypeError("key: expected bytes, but got %r" % type(key).__name__)
 
         if digestmod is None:
             import hashlib