diff --git a/designateclient/cli/base.py b/designateclient/cli/base.py
index d8464327..63afe337 100644
--- a/designateclient/cli/base.py
+++ b/designateclient/cli/base.py
@@ -20,10 +20,11 @@ from cliff.show import ShowOne
 from designateclient import exceptions
 from designateclient import utils
 from designateclient.v1 import Client
+import six
 
 
+@six.add_metaclass(abc.ABCMeta)
 class Command(CliffCommand):
-    __metaclass__ = abc.ABCMeta
 
     def run(self, parsed_args):
         client_args = {
diff --git a/designateclient/v1/base.py b/designateclient/v1/base.py
index f331fecd..bb1f88d8 100644
--- a/designateclient/v1/base.py
+++ b/designateclient/v1/base.py
@@ -14,17 +14,18 @@
 # License for the specific language governing permissions and limitations
 # under the License.
 import abc
+import six
 
 
+@six.add_metaclass(abc.ABCMeta)
 class Controller(object):
-    __metaclass__ = abc.ABCMeta
 
     def __init__(self, client):
         self.client = client
 
 
+@six.add_metaclass(abc.ABCMeta)
 class CrudController(Controller):
-    __metaclass__ = abc.ABCMeta
 
     @abc.abstractmethod
     def list(self, *args, **kw):
diff --git a/requirements.txt b/requirements.txt
index 1dcdc3fe..1e886786 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -3,4 +3,5 @@ jsonschema>=2.0.0,<3.0.0
 pbr>=0.6,<1.0
 python-keystoneclient>=0.6.0
 requests>=1.1
+six>=1.6.0
 stevedore>=0.14