diff --git a/apps/wei/forms/surveys/wei2021.py b/apps/wei/forms/surveys/wei2021.py
index 4b16928b..e515d447 100644
--- a/apps/wei/forms/surveys/wei2021.py
+++ b/apps/wei/forms/surveys/wei2021.py
@@ -148,7 +148,7 @@ class WEISurvey2021(WEISurvey):
         buses = cls.get_algorithm_class().get_buses()
         return sum([cls.get_algorithm_class().get_bus_information(bus).scores[word] for bus in buses]) / buses.count()
 
-    @lru_cache
+    @lru_cache()
     def score(self, bus):
         if not self.is_complete():
             raise ValueError("Survey is not ended, can't calculate score")