optimisation de la liste des ip

services/admin.py

@@ -236,10 +236,7 @@ class IPResourceAdmin(admin.ModelAdmin):
     available_display.boolean = True
 
     def last_use(self, obj):
-        if obj.allocations.exists():
-            return obj.allocations.last().end
-        else:
-            return None
+        return obj.last_use
     last_use.short_description = 'Dernière utilisation'
     last_use.admin_order_field = 'last_use'