diff --git a/mu_map/dataset/normalization.py b/mu_map/dataset/normalization.py
index f233b4c87d9468ba96c344d4494f74bcc1ecf654..7ffa7ffaecac4d625a91e2625fded0e2aaa09566 100644
--- a/mu_map/dataset/normalization.py
+++ b/mu_map/dataset/normalization.py
@@ -1,3 +1,5 @@
+from typing import Tuple
+
 from torch import Tensor
 
 from mu_map.dataset.transform import Transform