diff --git a/test/test_run_modules/test_model_setup.py b/test/test_run_modules/test_model_setup.py
index 83fe409fbf9aa5237338daf88b479630da0e81f2..295954a7cf53927939d50de5a84d474cb1818026 100644
--- a/test/test_run_modules/test_model_setup.py
+++ b/test/test_run_modules/test_model_setup.py
@@ -139,6 +139,8 @@ class DummyData:
 
     def __init__(self, number_of_samples=np.random.randint(100, 150)):
         self.number_of_samples = number_of_samples
+        self._len = self.number_of_samples
+        self._len_upsampling = self.number_of_samples
 
     def __len__(self, upsampling=False):
         if upsampling is False: