diff --git a/mmdet/datasets/__init__.py b/mmdet/datasets/__init__.py
index 9c2948286fd5ec369c93ab18b42ebba7520ae470..2e72022bdade2ae441b05a83810788314f6caf6a 100644
--- a/mmdet/datasets/__init__.py
+++ b/mmdet/datasets/__init__.py
@@ -10,4 +10,3 @@ __all__ = [
     'build_dataloader', 'to_tensor', 'random_scale', 'show_ann',
     'get_dataset', 'ExtraAugmentation', 'ConcatDataset', 'RepeatDataset',
 ]
-
diff --git a/mmdet/datasets/utils.py b/mmdet/datasets/utils.py
index b9ee9a8f240352859ae2c2e4ed4411ff59dbbcb3..8fdba7f211f26c8dffd95b4ae728a8e11576d305 100644
--- a/mmdet/datasets/utils.py
+++ b/mmdet/datasets/utils.py
@@ -76,7 +76,8 @@ def show_ann(coco, img, ann_info):
 
 def get_dataset(data_cfg):
     if data_cfg['type'] == 'RepeatDataset':
-        return RepeatDataset(get_dataset(data_cfg['dataset']), data_cfg['times'])
+        return RepeatDataset(
+            get_dataset(data_cfg['dataset']), data_cfg['times'])
 
     if isinstance(data_cfg['ann_file'], (list, tuple)):
         ann_files = data_cfg['ann_file']