refactor for v4.1

Change-Id: Ic2241a54348143640d2d6ee8683b53f2ec243aab
diff --git a/xos/tosca/resources/vmmevendor.py b/xos/tosca/resources/vmmevendor.py
index 3997db7..9fed878 100644
--- a/xos/tosca/resources/vmmevendor.py
+++ b/xos/tosca/resources/vmmevendor.py
@@ -13,7 +13,7 @@
 # limitations under the License.
 
 from xosresource import XOSResource
-from core.models import Tenant
+from core.models import ServiceInstance
 from services.vmme.models import VMMEVendor
 
 class XOSVMMEVendor(XOSResource):
@@ -27,7 +27,7 @@
 
         tenant_name = self.get_requirement("tosca.relationships.VendorOfTenant", throw_exception=throw_exception)
         if tenant_name:
-            args["provider_tenant"] = self.get_xos_object(Tenant, throw_exception=throw_exception, name=tenant_name)
+            args["provider_tenant"] = self.get_xos_object(ServiceInstance, throw_exception=throw_exception, name=tenant_name)
 
         return args