removing plural from model names. some cleanup
diff --git a/planetstack/model_policies/model_policy_Slice.py b/planetstack/model_policies/model_policy_Slice.py
index 0d83d68..37129a3 100644
--- a/planetstack/model_policies/model_policy_Slice.py
+++ b/planetstack/model_policies/model_policy_Slice.py
@@ -1,64 +1,59 @@
 
 def handle(slice):
-	from core.models import Controller,ControllerSlices,Controller,Network,NetworkSlice,NetworkTemplate
-	from collections import defaultdict
-	ctrl_site_deployments = SiteDeployments.objects.all()
-	
-	slice_controllers = ControllerSlices.objects.all()
-	slice_deploy_lookup = defaultdict(list)
-	for slice_controller in slice_controllers:
-		slice_deploy_lookup[slice_controller.slice].append(slice_controller)
-	
-        all_controllers = Controller.objects.all() 
-	for expected_controller in all_controllers:
-		if slice not in slice_deploy_lookup or \
-		   expected_controller not in slice_deploy_lookup[slice]:
-			sd = ControllerSlices(slice=slice, controller=expected_controller)
-			sd.save()
+    from core.models import Controller, ControllerSlice, SiteDeployment, Network, NetworkSlice,NetworkTemplate
+    from collections import defaultdict
+    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:
+            sd = ControllerSlice(slice=slice, controller=controller_controller)
+            sd.save()
 
-	# make sure slice has at least 1 public and 1 private networkd
-	public_nets = []
-	private_net = None
-	networks = Network.objects.filter(owner=slice)
-	for network in networks:
-		if network.template.name == 'Public dedicated IPv4':
-			public_nets.append(network)
-		elif network.template.name == 'Public shared IPv4':
-			public_nets.append(network)
-		elif network.template.name == 'Private':
-			private_net = network
-	if not public_nets:
+    # make sure slice has at least 1 public and 1 private networkd
+    public_nets = []
+    private_net = None
+    networks = Network.objects.filter(owner=slice)
+    for network in networks:
+        if network.template.name == 'Public dedicated IPv4':
+            public_nets.append(network)
+        elif network.template.name == 'Public shared IPv4':
+            public_nets.append(network)
+        elif network.template.name == 'Private':
+            private_net = network
+    if not public_nets:
                 # ensure there is at least one public network, and default it to dedicated
-		nat_net = Network(
-          	    name = slice.name+'-nat',
-             	    template = NetworkTemplate.objects.get(name='Public shared IPv4'),
-          	    owner = slice
-      		    )
-		nat_net.save()
-                public_nets.append(nat_net)
+        nat_net = Network(
+                name = slice.name+'-nat',
+                    template = NetworkTemplate.objects.get(name='Public shared IPv4'),
+                owner = slice
+                )
+        nat_net.save()
+        public_nets.append(nat_net)
 
-	if not private_net:
-        	private_net = Network(
-          	name = slice.name+'-private',
-          	template = NetworkTemplate.objects.get(name='Private'),
-          	owner = slice
-      		)
-      		private_net.save()
-	# create slice networks
-	public_net_slice = None
-	private_net_slice = None
-	net_slices = NetworkSlice.objects.filter(slice=slice, network__in=[private_net]+public_nets)
-	for net_slice in net_slices:
-		if net_slice.network in public_nets:
-			public_net_slice = net_slice
-		elif net_slice.network == private_net:
-			private_net_slice = net_slice
-	if not public_net_slice:
-		public_net_slice = NetworkSlice(slice=slice, network=public_nets[0])
-		public_net_slice.save()
-	if not private_net_slice:
-		private_net_slice = NetworkSlice(slice=slice, network=private_net)
-		private_net_slice.save()
+    if not private_net:
+        private_net = Network(
+        name = slice.name+'-private',
+        template = NetworkTemplate.objects.get(name='Private'),
+        owner = slice
+        )
+        private_net.save()
+    # create slice networks
+    public_net_slice = None
+    private_net_slice = None
+    net_slices = NetworkSlice.objects.filter(slice=slice, network__in=[private_net]+public_nets)
+    for net_slice in net_slices:
+        if net_slice.network in public_nets:
+            public_net_slice = net_slice
+        elif net_slice.network == private_net:
+            private_net_slice = net_slice
+    if not public_net_slice:
+        public_net_slice = NetworkSlice(slice=slice, network=public_nets[0])
+        public_net_slice.save()
+    if not private_net_slice:
+        private_net_slice = NetworkSlice(slice=slice, network=private_net)
+        private_net_slice.save()