diff --git a/utils/timefeatures.py b/utils/timefeatures.py
index 1e2c65b..470cef1 100644
--- a/utils/timefeatures.py
+++ b/utils/timefeatures.py
@@ -20,7 +20,7 @@ class TimeFeature:
 
 class SecondOfMinute(TimeFeature):
     """Minute of hour encoded as value between [-0.5, 0.5]"""
-    def __call__(self, index: pd.DatetimeIndex) -> np.ndarray:
+    def __call__(self, index: pd.DatetimeIndex) -> mnp.ndarray:
         return index.second / 59.0 - 0.5
 
 class MinuteOfHour(TimeFeature):