diff --git a/tests/artifacts/datasets/save_dataset_to_safetensors.py b/tests/artifacts/datasets/save_dataset_to_safetensors.py
index 2579a6e53..3df42f35c 100644
--- a/tests/artifacts/datasets/save_dataset_to_safetensors.py
+++ b/tests/artifacts/datasets/save_dataset_to_safetensors.py
@@ -53,11 +53,7 @@ def save_dataset_to_safetensors(output_dir, repo_id="lerobot/pusht"):
 
     # save 2 frames at the middle of first episode
     i = int(
-        (
-            dataset.meta.episodes["dataset_to_index"][0]
-            - dataset.meta.episodes["dataset_from_index"][0]
-        )
-        / 2
+        (dataset.meta.episodes["dataset_to_index"][0] - dataset.meta.episodes["dataset_from_index"][0]) / 2
     )
     save_file(dataset[i], repo_dir / f"frame_{i}.safetensors")
     save_file(dataset[i + 1], repo_dir / f"frame_{i + 1}.safetensors")