Skip some tests for py3 since boto is not compatible yet.

tests/helpers.py

@@ -1,6 +1,7 @@
 from __future__ import unicode_literals
 import boto
 from nose.plugins.skip import SkipTest
+import six
 
 
 def version_tuple(v):
@@ -23,3 +24,10 @@ class requires_boto_gte(object):
         if boto_version >= required:
             return test
         return skip_test
+
+
+class disable_on_py3(object):
+    def __call__(self, test):
+        if not six.PY3:
+            return test
+        return skip_test