Remove six from drivers module

This is part of the steps to remove usage of six library, which is no
longer needed since python 2 support was removed.

Change-Id: If6fb372f72a469e55e956e127c49863b5a557552

magnum/drivers/common/driver.py

@@ -13,7 +13,6 @@
 # under the License.
 
 import abc
-import six
 
 import importlib_metadata as metadata
 from oslo_config import cfg
@@ -26,8 +25,7 @@ from magnum.objects import cluster_template
 CONF = cfg.CONF
 
 
-@six.add_metaclass(abc.ABCMeta)
-class Driver(object):
+class Driver(object, metaclass=abc.ABCMeta):
 
     definitions = None
 

magnum/drivers/heat/driver.py

@@ -13,7 +13,6 @@
 import abc
 import collections
 import os
-import six
 
 from string import ascii_letters
 from string import digits
@@ -47,8 +46,7 @@ NodeGroupStatus = collections.namedtuple('NodeGroupStatus',
                                          'name status reason is_default')
 
 
-@six.add_metaclass(abc.ABCMeta)
-class HeatDriver(driver.Driver):
+class HeatDriver(driver.Driver, metaclass=abc.ABCMeta):
     """Base Driver class for using Heat
 
        Abstract class for implementing Drivers that leverage OpenStack Heat for

magnum/drivers/heat/k8s_fedora_template_def.py

@@ -23,7 +23,6 @@ from magnum.drivers.heat import k8s_template_def
 from magnum.drivers.heat import template_def
 from magnum.i18n import _
 from oslo_config import cfg
-import six
 
 CONF = cfg.CONF
 
@@ -165,8 +164,7 @@ class K8sFedoraTemplateDefinition(k8s_template_def.K8sTemplateDefinition):
             extra_params['cert_manager_api'] = cert_manager_api
             ca_cert = cert_manager.get_cluster_ca_certificate(cluster,
                                                               context=context)
-            if six.PY3 and isinstance(ca_cert.get_private_key_passphrase(),
-                                      six.text_type):
+            if isinstance(ca_cert.get_private_key_passphrase(), str):
                 extra_params['ca_key'] = x509.decrypt_key(
                     ca_cert.get_private_key(),
                     ca_cert.get_private_key_passphrase().encode()

magnum/drivers/heat/template_def.py

@@ -18,7 +18,6 @@ from oslo_log import log as logging
 from oslo_utils import strutils
 from oslo_utils import uuidutils
 import requests
-import six
 
 from magnum.common import clients
 from magnum.common import exception
@@ -188,8 +187,7 @@ class NodeGroupOutputMapping(OutputMapping):
         return None
 
 
-@six.add_metaclass(abc.ABCMeta)
-class TemplateDefinition(object):
+class TemplateDefinition(object, metaclass=abc.ABCMeta):
     """A mapping between Magnum objects and Heat templates.
 
     A TemplateDefinition is essentially a mapping between Magnum objects

magnum/drivers/k8s_fedora_coreos_v1/template_def.py

@@ -13,7 +13,7 @@
 # under the License.
 
 import os
-import six.moves.urllib.parse as urlparse
+from urllib import parse as urlparse
 
 from magnum.common import utils
 import magnum.conf