diff --git a/paddlespeech/s2t/exps/deepspeech2/bin/deploy/runtime.py b/paddlespeech/s2t/exps/deepspeech2/bin/deploy/runtime.py
index ccb85906a917a0db882c9e1e4eb53b25514c6d9a..5755a5f101c18927aff975262d627f81a74fb783 100644
--- a/paddlespeech/s2t/exps/deepspeech2/bin/deploy/runtime.py
+++ b/paddlespeech/s2t/exps/deepspeech2/bin/deploy/runtime.py
@@ -19,8 +19,8 @@ import paddle
 from paddle.inference import Config
 from paddle.inference import create_predictor
 from paddle.io import DataLoader
-
 from yacs.config import CfgNode
+
 from paddlespeech.s2t.io.collator import SpeechCollator
 from paddlespeech.s2t.io.dataset import ManifestDataset
 from paddlespeech.s2t.models.ds2 import DeepSpeech2Model
diff --git a/paddlespeech/s2t/exps/deepspeech2/bin/deploy/server.py b/paddlespeech/s2t/exps/deepspeech2/bin/deploy/server.py
index 85c2466f5809602c33f7219c10665a6c224d33fe..0d0b4f2197c05383285bbf590f53f334d134c969 100644
--- a/paddlespeech/s2t/exps/deepspeech2/bin/deploy/server.py
+++ b/paddlespeech/s2t/exps/deepspeech2/bin/deploy/server.py
@@ -17,8 +17,8 @@ import functools
 import numpy as np
 import paddle
 from paddle.io import DataLoader
-
 from yacs.config import CfgNode
+
 from paddlespeech.s2t.io.collator import SpeechCollator
 from paddlespeech.s2t.io.dataset import ManifestDataset
 from paddlespeech.s2t.models.ds2 import DeepSpeech2Model
diff --git a/paddlespeech/s2t/exps/deepspeech2/bin/export.py b/paddlespeech/s2t/exps/deepspeech2/bin/export.py
index 090b5fabffe71e558acd3777fd49bc75997a1663..ee013d79e6ed3d39516ee65d5c4df5ec30a24b42 100644
--- a/paddlespeech/s2t/exps/deepspeech2/bin/export.py
+++ b/paddlespeech/s2t/exps/deepspeech2/bin/export.py
@@ -13,6 +13,7 @@
 # limitations under the License.
 """Export for DeepSpeech2 model."""
 from yacs.config import CfgNode
+
 from paddlespeech.s2t.exps.deepspeech2.model import DeepSpeech2Tester as Tester
 from paddlespeech.s2t.training.cli import default_argument_parser
 from paddlespeech.s2t.utils.utility import print_arguments
diff --git a/paddlespeech/s2t/exps/deepspeech2/bin/test_export.py b/paddlespeech/s2t/exps/deepspeech2/bin/test_export.py
index 176028ed89eee9867be3dbbbcd923f5823eb5309..707eb9e1bc26204fe5b6a9070e02f7ad95d5f334 100644
--- a/paddlespeech/s2t/exps/deepspeech2/bin/test_export.py
+++ b/paddlespeech/s2t/exps/deepspeech2/bin/test_export.py
@@ -13,6 +13,7 @@
 # limitations under the License.
 """Evaluation for DeepSpeech2 model."""
 from yacs.config import CfgNode
+
 from paddlespeech.s2t.exps.deepspeech2.model import DeepSpeech2ExportTester as ExportTester
 from paddlespeech.s2t.training.cli import default_argument_parser
 from paddlespeech.s2t.utils.utility import print_arguments
diff --git a/paddlespeech/s2t/exps/deepspeech2/bin/train.py b/paddlespeech/s2t/exps/deepspeech2/bin/train.py
index 5e8c0fffec586943d17a7bf03ff360bfc8985fdf..09e8662f1ce75ff351d7981dc1c4382082f9b61a 100644
--- a/paddlespeech/s2t/exps/deepspeech2/bin/train.py
+++ b/paddlespeech/s2t/exps/deepspeech2/bin/train.py
@@ -13,8 +13,8 @@
 # limitations under the License.
 """Trainer for DeepSpeech2 model."""
 from paddle import distributed as dist
-
 from yacs.config import CfgNode
+
 from paddlespeech.s2t.exps.deepspeech2.model import DeepSpeech2Trainer as Trainer
 from paddlespeech.s2t.training.cli import default_argument_parser
 from paddlespeech.s2t.utils.utility import print_arguments
diff --git a/paddlespeech/s2t/exps/u2/bin/export.py b/paddlespeech/s2t/exps/u2/bin/export.py
index 3907cebdd1f342fac180a1fcb2c9b076b9eb26ae..592b12379be7648377ad3c450f2b608610121fbe 100644
--- a/paddlespeech/s2t/exps/u2/bin/export.py
+++ b/paddlespeech/s2t/exps/u2/bin/export.py
@@ -13,6 +13,7 @@
 # limitations under the License.
 """Export for U2 model."""
 from yacs.config import CfgNode
+
 from paddlespeech.s2t.exps.u2.model import U2Tester as Tester
 from paddlespeech.s2t.training.cli import default_argument_parser
 from paddlespeech.s2t.utils.utility import print_arguments
diff --git a/paddlespeech/s2t/exps/u2/bin/train.py b/paddlespeech/s2t/exps/u2/bin/train.py
index d562278f5fe8cffa24541d2dbf2e52e82f8bff1e..53c223283f180397e69b6a5290a4572e5a76cc41 100644
--- a/paddlespeech/s2t/exps/u2/bin/train.py
+++ b/paddlespeech/s2t/exps/u2/bin/train.py
@@ -16,8 +16,8 @@ import cProfile
 import os
 
 from paddle import distributed as dist
-
 from yacs.config import CfgNode
+
 from paddlespeech.s2t.exps.u2.model import U2Trainer as Trainer
 from paddlespeech.s2t.training.cli import default_argument_parser
 from paddlespeech.s2t.utils.utility import print_arguments
diff --git a/paddlespeech/s2t/exps/u2_kaldi/model.py b/paddlespeech/s2t/exps/u2_kaldi/model.py
index 780c5c08170183ff220f85bbacc76052a0b69a4b..d7a9f460bd10366c17eb8830881afdad91c1a493 100644
--- a/paddlespeech/s2t/exps/u2_kaldi/model.py
+++ b/paddlespeech/s2t/exps/u2_kaldi/model.py
@@ -42,6 +42,7 @@ from paddlespeech.s2t.utils.utility import UpdateConfig
 
 logger = Log(__name__).getlog()
 
+
 class U2Trainer(Trainer):
     def __init__(self, config, args):
         super().__init__(config, args)
diff --git a/paddlespeech/s2t/exps/u2_st/bin/export.py b/paddlespeech/s2t/exps/u2_st/bin/export.py
index 1bc4e1f3c87b5ac8cca58642a402399944d4cb0e..c641152fe4bd75b5c72617370b02b29cc79f0435 100644
--- a/paddlespeech/s2t/exps/u2_st/bin/export.py
+++ b/paddlespeech/s2t/exps/u2_st/bin/export.py
@@ -13,6 +13,7 @@
 # limitations under the License.
 """Export for U2 model."""
 from yacs.config import CfgNode
+
 from paddlespeech.s2t.exps.u2_st.model import U2STTester as Tester
 from paddlespeech.s2t.training.cli import default_argument_parser
 from paddlespeech.s2t.utils.utility import print_arguments
diff --git a/paddlespeech/s2t/exps/u2_st/model.py b/paddlespeech/s2t/exps/u2_st/model.py
index ca2c2c1daa1aedf5066c9445f203966a2f6c9f7c..ecb9a08badfd55cdee5cccea779d3ecf9c7f144a 100644
--- a/paddlespeech/s2t/exps/u2_st/model.py
+++ b/paddlespeech/s2t/exps/u2_st/model.py
@@ -208,8 +208,7 @@ class U2STTrainer(Trainer):
                                 k.split(',')) == 2 else ""
                             msg += ","
                         msg = msg[:-1]  # remove the last ","
-                        if (batch_index + 1
-                            ) % self.config.log_interval == 0:
+                        if (batch_index + 1) % self.config.log_interval == 0:
                             logger.info(msg)
                 except Exception as e:
                     logger.error(e)
@@ -260,7 +259,8 @@ class U2STTrainer(Trainer):
                 batch_frames_in=0,
                 batch_frames_out=0,
                 batch_frames_inout=0,
-                preprocess_conf=config.preprocess_config,  # aug will be off when train_mode=False
+                preprocess_conf=config.
+                preprocess_config,  # aug will be off when train_mode=False
                 n_iter_processes=config.num_workers,
                 subsampling_factor=1,
                 load_aux_output=load_transcript,
@@ -281,7 +281,8 @@ class U2STTrainer(Trainer):
                 batch_frames_in=0,
                 batch_frames_out=0,
                 batch_frames_inout=0,
-                preprocess_conf=config.preprocess_config,  # aug will be off when train_mode=False
+                preprocess_conf=config.
+                preprocess_config,  # aug will be off when train_mode=False
                 n_iter_processes=config.num_workers,
                 subsampling_factor=1,
                 load_aux_output=load_transcript,
@@ -290,7 +291,8 @@ class U2STTrainer(Trainer):
             logger.info("Setup train/valid Dataloader!")
         else:
             # test dataset, return raw text
-            decode_batch_size = config.get('decode',dict()).get('decode_batch_size', 1)
+            decode_batch_size = config.get('decode', dict()).get(
+                'decode_batch_size', 1)
             self.test_loader = BatchDataLoader(
                 json_file=config.test_manifest,
                 train_mode=False,
@@ -305,7 +307,8 @@ class U2STTrainer(Trainer):
                 batch_frames_in=0,
                 batch_frames_out=0,
                 batch_frames_inout=0,
-                preprocess_conf=config.preprocess_config,  # aug will be off when train_mode=False
+                preprocess_conf=config.
+                preprocess_config,  # aug will be off when train_mode=False
                 n_iter_processes=config.num_workers,
                 subsampling_factor=1,
                 num_encs=1,
diff --git a/paddlespeech/s2t/models/ds2/deepspeech2.py b/paddlespeech/s2t/models/ds2/deepspeech2.py
index ddc3612d92634861533ade9605eb2afbc8773572..15cadd38e17f9e586737e85607aee2c3f2601cb3 100644
--- a/paddlespeech/s2t/models/ds2/deepspeech2.py
+++ b/paddlespeech/s2t/models/ds2/deepspeech2.py
@@ -119,6 +119,7 @@ class DeepSpeech2Model(nn.Layer):
              before softmax) and a ctc cost layer.
     :rtype: tuple of LayerOutput
     """
+
     def __init__(self,
                  feat_size,
                  dict_size,
diff --git a/paddlespeech/s2t/models/ds2_online/deepspeech2.py b/paddlespeech/s2t/models/ds2_online/deepspeech2.py
index aae77f74868765c2a1b3b762cab183d48b2e1ce3..6451118a8a6492ecbfb83979262c5b4790a6c92c 100644
--- a/paddlespeech/s2t/models/ds2_online/deepspeech2.py
+++ b/paddlespeech/s2t/models/ds2_online/deepspeech2.py
@@ -243,6 +243,7 @@ class DeepSpeech2ModelOnline(nn.Layer):
              before softmax) and a ctc cost layer.
     :rtype: tuple of LayerOutput
     """
+
     def __init__(
             self,
             feat_size,
diff --git a/paddlespeech/s2t/models/u2/u2.py b/paddlespeech/s2t/models/u2/u2.py
index 26e81acf64b3ce79e2a4c5aa09b907c47604f8b3..dc3072c620dca2efe2f7957356a5e48cf7146342 100644
--- a/paddlespeech/s2t/models/u2/u2.py
+++ b/paddlespeech/s2t/models/u2/u2.py
@@ -59,6 +59,7 @@ logger = Log(__name__).getlog()
 
 class U2BaseModel(ASRInterface, nn.Layer):
     """CTC-Attention hybrid Encoder-Decoder model"""
+
     def __init__(self,
                  vocab_size: int,
                  encoder: TransformerEncoder,
diff --git a/paddlespeech/s2t/models/u2_st/u2_st.py b/paddlespeech/s2t/models/u2_st/u2_st.py
index 1c5596bac97f1591a471d23e006318aa079bcd4a..bcade95ee33f1d77b882e152da48049f831275f2 100644
--- a/paddlespeech/s2t/models/u2_st/u2_st.py
+++ b/paddlespeech/s2t/models/u2_st/u2_st.py
@@ -51,6 +51,7 @@ logger = Log(__name__).getlog()
 
 class U2STBaseModel(nn.Layer):
     """CTC-Attention hybrid Encoder-Decoder model"""
+
     def __init__(self,
                  vocab_size: int,
                  encoder: TransformerEncoder,
diff --git a/paddlespeech/s2t/modules/ctc.py b/paddlespeech/s2t/modules/ctc.py
index 4a2e4f24fabf6904c2a6b2bc373f510609759096..6e9655799c42f5c2deb41bed873dd88774261ec4 100644
--- a/paddlespeech/s2t/modules/ctc.py
+++ b/paddlespeech/s2t/modules/ctc.py
@@ -39,7 +39,6 @@ except ImportError:
     except Exception as e:
         logger.info("paddlespeech_ctcdecoders not installed!")
 
-
 __all__ = ['CTCDecoder']