set creator from caller in TenantWithContainer; delete duplicate creator.setter method
diff --git a/xos/core/models/service.py b/xos/core/models/service.py
index 135dce9..e33e7bc 100644
--- a/xos/core/models/service.py
+++ b/xos/core/models/service.py
@@ -599,14 +599,6 @@
 
         raise XOSProgrammingError("No VPCE image (looked for %s)" % str(look_for_images))
 
-    @creator.setter
-    def creator(self, value):
-        if value:
-            value = value.id
-        if (value != self.get_attribute("creator_id", None)):
-            self.cached_creator=None
-        self.set_attribute("creator_id", value)
-
     def save_instance(self, instance):
         # Override this function to do custom pre-save or post-save processing,
         # such as creating ports for containers.
@@ -694,6 +686,11 @@
                 self.instance.delete()
             self.instance = None
 
+    def save(self, *args, **kwargs):
+        if (not self.creator) and (hasattr(self, "caller")) and (self.caller):
+            self.creator = self.caller
+        super(TenantWithContainer, self).save(*args, **kwargs)
+
 class CoarseTenant(Tenant):
     """ TODO: rename "CoarseTenant" --> "StaticTenant" """
     class Meta: