diff --git a/oioioi/szkopul/tests.py b/oioioi/szkopul/tests.py
index 972da90aa..d664e840d 100644
--- a/oioioi/szkopul/tests.py
+++ b/oioioi/szkopul/tests.py
@@ -1,4 +1,4 @@
-# coding: utf8
+# coding: utf-8
 from __future__ import print_function
 
 from django.test.utils import override_settings