CORD-1354 fix NetworkSlice and ControllerSite created when they already exists

Change-Id: Ic37464dac40b3e5f92b705f30337ddc77df54ac0
diff --git a/xos/synchronizer/model_policies/model_policy_Slice.py b/xos/synchronizer/model_policies/model_policy_Slice.py
index 68aa596..dfc136a 100644
--- a/xos/synchronizer/model_policies/model_policy_Slice.py
+++ b/xos/synchronizer/model_policies/model_policy_Slice.py
@@ -85,10 +85,11 @@
         net_slices = [x for x in net_slices if x.network_id in public_net_ids+private_net_ids]
 
         for net_slice in net_slices:
-            if net_slice.network in public_nets:
+            if net_slice.network.id in public_nets_ids:
                 public_net_slice = net_slice
-            elif net_slice.network in private_nets:
+            elif net_slice.network.id in private_nets_ids:
                 private_net_slice = net_slice
+                
         if support_nat_net and (not public_net_slice):
             public_net_slice = NetworkSlice(slice=slice, network=public_nets[0])
             public_net_slice.save()