Rename zone.region to zone.region_name since it returns a string instead

of an object.

cloudbridge/cloud/interfaces/resources.py

@@ -1303,7 +1303,7 @@ class PlacementZone(CloudResource):
         pass
 
     @abstractproperty
-    def region(self):
+    def region_name(self):
         """
         A region this placement zone is associated with.
 

cloudbridge/cloud/providers/aws/resources.py

@@ -135,7 +135,7 @@ class AWSPlacementZone(BasePlacementZone):
         return self._aws_zone
 
     @property
-    def region(self):
+    def region_name(self):
         """
         Get the region that this zone belongs to.
 

cloudbridge/cloud/providers/openstack/resources.py

@@ -129,7 +129,7 @@ class OpenStackPlacementZone(BasePlacementZone):
         return self._os_zone
 
     @property
-    def region(self):
+    def region_name(self):
         """
         Get the region that this zone belongs to.
 

test/test_region_service.py

@@ -1,3 +1,5 @@
+import six
+
 from cloudbridge.cloud.interfaces import Region
 from test.helpers import ProviderTestBase
 import test.helpers as helpers
@@ -65,7 +67,7 @@ class CloudRegionServiceTestCase(ProviderTestBase):
             for zone in region.zones:
                 self.assertTrue(zone.id)
                 self.assertTrue(zone.name)
-                self.assertTrue(zone.region)
+                self.assertIsInstance(zone.region_name, six.string_types)
                 if test_zone == zone.name:
                     zone_find_count += 1
         # TODO: Can't do a check for zone_find_count == 1 because Moto