diff --git a/egs/aishell/ASR/local/prepare_lang.py b/egs/aishell/ASR/local/prepare_lang.py
index 8c208e10d..e5ae89ec4 100755
--- a/egs/aishell/ASR/local/prepare_lang.py
+++ b/egs/aishell/ASR/local/prepare_lang.py
@@ -317,8 +317,9 @@ def lexicon_to_fst(
 
 def get_args():
     parser = argparse.ArgumentParser()
-    parser.add_argument("--lang-dir", type=str,
-                        help="The lang dir, data/lang_phone")
+    parser.add_argument(
+        "--lang-dir", type=str, help="The lang dir, data/lang_phone"
+    )
     return parser.parse_args()
 
 
diff --git a/egs/aishell/ASR/tdnn_lstm_ctc/asr_datamodule.py b/egs/aishell/ASR/tdnn_lstm_ctc/asr_datamodule.py
index 3a10f39b6..65caa656e 100644
--- a/egs/aishell/ASR/tdnn_lstm_ctc/asr_datamodule.py
+++ b/egs/aishell/ASR/tdnn_lstm_ctc/asr_datamodule.py
@@ -339,18 +339,17 @@ class AishellAsrDataModule:
     @lru_cache()
     def train_cuts(self) -> CutSet:
         logging.info("About to get train cuts")
-        cuts_train = load_manifest(self.args.manifest_dir /
-                                   "cuts_train.json.gz")
+        cuts_train = load_manifest(
+            self.args.manifest_dir / "cuts_train.json.gz"
+        )
         return cuts_train
 
     @lru_cache()
     def valid_cuts(self) -> CutSet:
         logging.info("About to get dev cuts")
-        return load_manifest(self.args.manifest_dir /
-                             "cuts_dev.json.gz")
+        return load_manifest(self.args.manifest_dir / "cuts_dev.json.gz")
 
     @lru_cache()
     def test_cuts(self) -> List[CutSet]:
         logging.info("About to get test cuts")
-        return load_manifest(self.args.manifest_dir /
-                             "cuts_test.json.gz")
+        return load_manifest(self.args.manifest_dir / "cuts_test.json.gz")
diff --git a/egs/aishell/ASR/transducer_stateless/train.py b/egs/aishell/ASR/transducer_stateless/train.py
index 7de38ed41..7da8e28a1 100755
--- a/egs/aishell/ASR/transducer_stateless/train.py
+++ b/egs/aishell/ASR/transducer_stateless/train.py
@@ -555,7 +555,7 @@ def run(rank, world_size, args):
     graph_compiler = CharCtcTrainingGraphCompiler(
         lexicon=lexicon,
         device=device,
-        oov='<unk>',
+        oov="<unk>",
     )
 
     params.blank_id = graph_compiler.texts_to_ids("<blk>")[0][0]