diff --git a/lerobot/common/datasets/factory.py b/lerobot/common/datasets/factory.py
index f0e6abe7..416074fe 100644
--- a/lerobot/common/datasets/factory.py
+++ b/lerobot/common/datasets/factory.py
@@ -81,8 +81,8 @@ def make_dataset(cfg: TrainPipelineConfig) -> LeRobotDataset | MultiLeRobotDatas
     image_transforms = (
         ImageTransforms(cfg.dataset.image_transforms) if cfg.dataset.image_transforms.enable else None
     )
-    if cfg.dataset.repo_id.startswith('['):
-        datasets = cfg.dataset.repo_id.strip('[]').split(',')
+    if cfg.dataset.repo_id.startswith("["):
+        datasets = cfg.dataset.repo_id.strip("[]").split(",")
         datasets = [x.strip() for x in datasets]
         delta_timestamps = {}
         for ds in datasets:
@@ -98,7 +98,7 @@ def make_dataset(cfg: TrainPipelineConfig) -> LeRobotDataset | MultiLeRobotDatas
         )
         logging.info(
             "Multiple datasets were provided. Applied the following index mapping to the provided datasets: "
-            f"{pformat(dataset.repo_id_to_index , indent=2)}"
+            f"{pformat(dataset.repo_id_to_index, indent=2)}"
         )
     else:
         ds_meta = LeRobotDatasetMetadata(cfg.dataset.repo_id)
diff --git a/lerobot/common/logger.py b/lerobot/common/logger.py
index 18458ae6..b874f4ba 100644
--- a/lerobot/common/logger.py
+++ b/lerobot/common/logger.py
@@ -49,8 +49,8 @@ def cfg_to_group(cfg: TrainPipelineConfig, return_list: bool = False) -> list[st
     """Return a group name for logging. Optionally returns group name as list."""
     # TODO: these were used to support multirepodataset in the past - think how they could be supported in new way?
     dataset_tag = cfg.dataset.repo_id
-    if dataset_tag.startswith('['):
-        tags = dataset_tag.strip('[]').split(',')
+    if dataset_tag.startswith("["):
+        tags = dataset_tag.strip("[]").split(",")
         dataset_tag = f"{tags[0].strip()}_and_more"
     lst = [
         f"policy:{cfg.policy.type}",