diff --git a/src/ifcopenshell-python/ifcopenshell/util/attribute.py b/src/ifcopenshell-python/ifcopenshell/util/attribute.py
index 2fa47589c1..b7a241c5f6 100644
--- a/src/ifcopenshell-python/ifcopenshell/util/attribute.py
+++ b/src/ifcopenshell-python/ifcopenshell/util/attribute.py
@@ -55,9 +55,9 @@ def get_primitive_type(
         return "binary"
 
 
-def get_enum_items(attribute):
+def get_enum_items(attribute: ifcopenshell_wrapper.attribute) -> tuple[str, ...]:
     return attribute.type_of_attribute().declared_type().enumeration_items()
 
 
-def get_select_items(attribute):
+def get_select_items(attribute: ifcopenshell_wrapper.attribute) -> tuple[ifcopenshell_wrapper.entity, ...]:
     return attribute.type_of_attribute().declared_type().select_list()