diff --git a/egs/aishell/ASR/conformer_ctc/.transformer.py.swp b/egs/aishell/ASR/conformer_ctc/.transformer.py.swp
deleted file mode 100644
index 8927c581a..000000000
Binary files a/egs/aishell/ASR/conformer_ctc/.transformer.py.swp and /dev/null differ
diff --git a/egs/aishell/ASR/conformer_ctc/transformer.py b/egs/aishell/ASR/conformer_ctc/transformer.py
index e45f898d3..d01fa29ef 100644
--- a/egs/aishell/ASR/conformer_ctc/transformer.py
+++ b/egs/aishell/ASR/conformer_ctc/transformer.py
@@ -42,7 +42,7 @@ class Transformer(nn.Module):
         normalize_before: bool = True,
         vgg_frontend: bool = False,
         use_feat_batchnorm: bool = False,
-        group-num: int = 6,
+        group_num: int = 6,
     ) -> None:
         """
         Args: