diff --git a/resource_multi_week_work_time_from_contracts/models/__init__.py b/resource_multi_week_work_time_from_contracts/models/__init__.py
index 7a85334a..54f6e2da 100644
--- a/resource_multi_week_work_time_from_contracts/models/__init__.py
+++ b/resource_multi_week_work_time_from_contracts/models/__init__.py
@@ -3,3 +3,4 @@
 # SPDX-License-Identifier: AGPL-3.0-or-later
 
 from . import resource_calendar
+from . import resource_mixin