diff --git a/topobenchmark/transforms/_utils.py b/topobenchmark/transforms/_utils.py
index f14d156e..c2e0750c 100644
--- a/topobenchmark/transforms/_utils.py
+++ b/topobenchmark/transforms/_utils.py
@@ -19,7 +19,9 @@ def discover_objs(package_path, condition=None):
         Dictionary mapping class names to their corresponding class objects.
     """
     if condition is None:
-        condition = lambda name, obj: True
+
+        def condition(name, obj):
+            return True
 
     objs = {}