diff --git a/src/fiber_package/entities/submodels.py b/src/fiber_package/entities/submodels.py
index c967c96..cc1e615 100644
--- a/src/fiber_package/entities/submodels.py
+++ b/src/fiber_package/entities/submodels.py
@@ -1,4 +1,4 @@
-from dataclass import dataclass, field
+from dataclasses import dataclass, field
 from datetime import date
 
 # always use @dataclass with slots=True for better performance