diff --git a/bob/learn/tensorflow/tests/data/db_to_tfrecords_config.py b/bob/learn/tensorflow/tests/data/db_to_tfrecords_config.py
index 637d8c551b37859242b3148918e478ee4eb7e87d..e711f9a4ca0e63aba01a08267af6c6af4ca7a12b 100644
--- a/bob/learn/tensorflow/tests/data/db_to_tfrecords_config.py
+++ b/bob/learn/tensorflow/tests/data/db_to_tfrecords_config.py
@@ -4,10 +4,7 @@ from bob.learn.tensorflow.data import dataset_using_generator
 mnist = tf.keras.datasets.mnist
 
 (x_train, y_train), (_, _) = mnist.load_data()
-samples = [
-    [a, b, c]
-    for a, b, c in zip(tf.keras.backend.arange(len(x_train)), x_train, y_train)
-]
+samples = zip(tf.keras.backend.arange(len(x_train)), x_train, y_train)
 
 
 def reader(sample):