diff --git a/scripts/simplify_network.py b/scripts/simplify_network.py
index 42f7daac..7ed17923 100644
--- a/scripts/simplify_network.py
+++ b/scripts/simplify_network.py
@@ -395,8 +395,10 @@ def simplify_links(n, costs, config, output, aggregation_strategies=dict()):
 def remove_stubs(n, costs, config, output, aggregation_strategies=dict()):
     logger.info("Removing stubs")
 
-    across_borders = config["clustering"]["simplify_network"].get("remove_stubs_across_borders", True)
-    matching_attrs = [] if across_borders else ['country']
+    across_borders = config["clustering"]["simplify_network"].get(
+        "remove_stubs_across_borders", True
+    )
+    matching_attrs = [] if across_borders else ["country"]
     busmap = busmap_by_stubs(n, matching_attrs)
 
     connection_costs_to_bus = _compute_connection_costs_to_bus(n, busmap, costs, config)