diff --git a/planetstack/model_policies/model_policy_Slice.py b/planetstack/model_policies/model_policy_Slice.py
index 1f58570..a9936bd 100644
--- a/planetstack/model_policies/model_policy_Slice.py
+++ b/planetstack/model_policies/model_policy_Slice.py
@@ -7,7 +7,7 @@
 
     controller_slices = ControllerSlice.objects.filter(slice=slice)
     existing_controllers = [cs.controller for cs in controller_slices] 
-    
+        
     all_controllers = Controller.objects.all() 
     for controller in all_controllers:
         if controller not in existing_controllers: