diff --git a/extensions-builtin/forge_legacy_preprocessors/scripts/legacy_preprocessor_loader.py b/extensions-builtin/forge_legacy_preprocessors/scripts/legacy_preprocessor_loader.py
index 7c3d16e9..c354c607 100644
--- a/extensions-builtin/forge_legacy_preprocessors/scripts/legacy_preprocessor_loader.py
+++ b/extensions-builtin/forge_legacy_preprocessors/scripts/legacy_preprocessor_loader.py
@@ -4,3 +4,7 @@
 # see also the forge_preprocessor_normalbae/scripts/preprocessor_normalbae for
 # how to make better implementation of preprocessors.
 # No newer preprocessors should be written in this legacy way.
+
+from legacy_preprocessors.preprocessor_meta import cn_preprocessor_modules, cn_preprocessor_unloadable
+
+a = 0