diff --git a/pyrival/__init__.py b/pyrival/__init__.py
index 992ea61..a636748 100644
--- a/pyrival/__init__.py
+++ b/pyrival/__init__.py
@@ -1,6 +1,6 @@
 from .version import version as __version__
 
 import os as _os
-for s in ('algebra', 'combinatorics', 'data_structures', 'geometry', 
+for _s in ('algebra', 'combinatorics', 'data_structures', 'geometry', 
           'graphs', 'linear_algebra', 'numerical', 'strings', 'misc', 'tools'):
-    __path__.append(_os.path.join(_os.path.dirname(__file__), s))
+    __path__.append(_os.path.join(_os.path.dirname(__file__), _s))