diff --git a/pupy/packages/all/pupyimporter.py b/pupy/packages/all/pupyimporter.py
index 19d1ac87..18e333df 100644
--- a/pupy/packages/all/pupyimporter.py
+++ b/pupy/packages/all/pupyimporter.py
@@ -304,7 +304,7 @@ class PupyPackageLoader:
 class PupyPackageFinderImportError(ImportError):
     pass
 
-class PupyPackageFinder:
+class PupyPackageFinder(object):
     def __init__(self, path=None):
         if path and not path.startswith('pupy://'):
             raise PupyPackageFinderImportError()