diff --git a/src/ifcopenshell-python/ifcopenshell/api/project/append_asset.py b/src/ifcopenshell-python/ifcopenshell/api/project/append_asset.py
index 67cd0a33c2..22eb022e99 100644
--- a/src/ifcopenshell-python/ifcopenshell/api/project/append_asset.py
+++ b/src/ifcopenshell-python/ifcopenshell/api/project/append_asset.py
@@ -479,7 +479,9 @@ class Usecase:
                 # IfcRelAssociatesClassification to openings! We only ever want
                 # to consider IfcFeatureElements in IfcRelVoidsElements and
                 # IfcRelProjectsElements.
-                if element.is_a() in ("IfcRelVoidsElement", "IfcRelProjectsElement") or not self.is_another_asset(attribute):
+                if element.is_a() in ("IfcRelVoidsElement", "IfcRelProjectsElement") or not self.is_another_asset(
+                    attribute
+                ):
                     new_attribute = self.add_element(attribute)
             elif isinstance(attribute, tuple) and attribute and isinstance(attribute[0], ifcopenshell.entity_instance):
                 new_attribute = []
diff --git a/src/ifcopenshell-python/test/api/project/test_append_asset.py b/src/ifcopenshell-python/test/api/project/test_append_asset.py
index ced9c8b251..399ee1fd04 100644
--- a/src/ifcopenshell-python/test/api/project/test_append_asset.py
+++ b/src/ifcopenshell-python/test/api/project/test_append_asset.py
@@ -415,10 +415,15 @@ class TestAppendAssetIFC2X3(test.bootstrap.IFC2X3):
         element = ifcopenshell.api.root.create_entity(library, ifc_class="IfcWall")
         opening = ifcopenshell.api.root.create_entity(library, ifc_class="IfcOpeningElement")
         classification = ifcopenshell.api.classification.add_classification(
-            library, classification="MyCustomClassification")
-        ifcopenshell.api.classification.add_reference(library,
-            products=[element, opening], classification=classification,
-            identification="W_01", name="Interior Walls")
+            library, classification="MyCustomClassification"
+        )
+        ifcopenshell.api.classification.add_reference(
+            library,
+            products=[element, opening],
+            classification=classification,
+            identification="W_01",
+            name="Interior Walls",
+        )
         ifcopenshell.api.project.append_asset(self.file, library=library, element=element)
         wall = self.file.by_type("IfcWall")[0]
         assert wall