diff --git a/dygraph/datasets/__init__.py b/dygraph/datasets/__init__.py
index 77dae995267f45ed2551b38ee6b1daf396fc0b8a..07fc961ccd5d8a984a4d0bc8485ac086d315820d 100644
--- a/dygraph/datasets/__init__.py
+++ b/dygraph/datasets/__init__.py
@@ -1,5 +1,4 @@
-# coding: utf8
-# Copyright (c) 2019 PaddlePaddle Authors. All Rights Reserve.
+# Copyright (c) 2020 PaddlePaddle Authors. All Rights Reserve.
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
diff --git a/dygraph/datasets/dataset.py b/dygraph/datasets/dataset.py
index 07bfdebd4ac106c0c8e28726590d3ec3aeb148a8..ad1c4bad3c67569fabf27baec2dfbd5f0b1b4b08 100644
--- a/dygraph/datasets/dataset.py
+++ b/dygraph/datasets/dataset.py
@@ -1,5 +1,4 @@
-# coding: utf8
-# Copyright (c) 2019 PaddlePaddle Authors. All Rights Reserve.
+# Copyright (c) 2020 PaddlePaddle Authors. All Rights Reserve.
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
diff --git a/dygraph/datasets/shared_queue/__init__.py b/dygraph/datasets/shared_queue/__init__.py
index 1662f739d491243a56d1cc70c13b7a91dbb46a7e..6486d9443295e800ac223dc1809359ae18c5f8b5 100644
--- a/dygraph/datasets/shared_queue/__init__.py
+++ b/dygraph/datasets/shared_queue/__init__.py
@@ -1,5 +1,4 @@
-# coding: utf8
-# Copyright (c) 2019 PaddlePaddle Authors. All Rights Reserve.
+# Copyright (c) 2020 PaddlePaddle Authors. All Rights Reserve.
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
diff --git a/dygraph/datasets/shared_queue/queue.py b/dygraph/datasets/shared_queue/queue.py
index 7a67f98de700e74e0361ae80cfe983c594f88024..d08bc1b369e411e8cde3ec5b57e0c485e1531a43 100644
--- a/dygraph/datasets/shared_queue/queue.py
+++ b/dygraph/datasets/shared_queue/queue.py
@@ -1,5 +1,4 @@
-# coding: utf8
-# Copyright (c) 2019 PaddlePaddle Authors. All Rights Reserve.
+# Copyright (c) 2020 PaddlePaddle Authors. All Rights Reserve.
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
diff --git a/dygraph/datasets/shared_queue/sharedmemory.py b/dygraph/datasets/shared_queue/sharedmemory.py
index 8df13752194575628d173ac6c96d40ae404590b5..e24cb8b3ba617d205941bbde1aadc1758675ba8c 100644
--- a/dygraph/datasets/shared_queue/sharedmemory.py
+++ b/dygraph/datasets/shared_queue/sharedmemory.py
@@ -1,5 +1,4 @@
-# coding: utf8
-# Copyright (c) 2019 PaddlePaddle Authors. All Rights Reserve.
+# Copyright (c) 2020 PaddlePaddle Authors. All Rights Reserve.
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
diff --git a/dygraph/main.py b/dygraph/main.py
index aeb861fb8ed10427657f2c3aee6fb04ef18321fe..6ae620e31ca613cddf9fa395bd2f5f3b4c1785c1 100644
--- a/dygraph/main.py
+++ b/dygraph/main.py
@@ -1,3 +1,17 @@
+# Copyright (c) 2020 PaddlePaddle Authors. All Rights Reserve.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
 from datasets import Dataset
 import transforms
 import paddle.fluid as fluid
diff --git a/dygraph/models/__init__.py b/dygraph/models/__init__.py
index c5bb8150e5af38deeee37716e345aff174c9064e..3f33a7b13073ba5017ce0702ef9cbc88aa70806d 100644
--- a/dygraph/models/__init__.py
+++ b/dygraph/models/__init__.py
@@ -1,5 +1,4 @@
-# coding: utf8
-# Copyright (c) 2019 PaddlePaddle Authors. All Rights Reserve.
+# Copyright (c) 2020 PaddlePaddle Authors. All Rights Reserve.
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
diff --git a/dygraph/models/unet.py b/dygraph/models/unet.py
index f4989e699aa18af18662e02dbb2611a86b7dfa86..cd286486fa9a6cf9f9077ec6f6eb32ee1dc0ef26 100644
--- a/dygraph/models/unet.py
+++ b/dygraph/models/unet.py
@@ -1,5 +1,4 @@
-# coding: utf8
-# Copyright (c) 2019 PaddlePaddle Authors. All Rights Reserve.
+# Copyright (c) 2020 PaddlePaddle Authors. All Rights Reserve.
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
diff --git a/dygraph/nets/__init__.py b/dygraph/nets/__init__.py
index 26d9fb22e1a39ed75217e0d82cd1b0f4eccb6e4c..bd79647abc0a625f21a28b230fd16ec38baab1d1 100644
--- a/dygraph/nets/__init__.py
+++ b/dygraph/nets/__init__.py
@@ -1,4 +1,3 @@
-# coding: utf8
 # Copyright (c) 2020 PaddlePaddle Authors. All Rights Reserve.
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
diff --git a/dygraph/nets/unet.py b/dygraph/nets/unet.py
index 5f5ed3b895dceb6ba44afff999280a4a6ccbf9cd..06db99091ab95268e52816c30ac5c060e4b1eee8 100644
--- a/dygraph/nets/unet.py
+++ b/dygraph/nets/unet.py
@@ -1,3 +1,17 @@
+# Copyright (c) 2020 PaddlePaddle Authors. All Rights Reserve.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
 from __future__ import absolute_import
 from __future__ import division
 from __future__ import print_function
diff --git a/dygraph/transforms/__init__.py b/dygraph/transforms/__init__.py
index b537d3216c5b72c75bf3e201304d20638f3ea706..9eccee953f212f691cbae771d66dc8179c0a8004 100644
--- a/dygraph/transforms/__init__.py
+++ b/dygraph/transforms/__init__.py
@@ -1,5 +1,4 @@
-# coding: utf8
-# Copyright (c) 2019 PaddlePaddle Authors. All Rights Reserve.
+# Copyright (c) 2020 PaddlePaddle Authors. All Rights Reserve.
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
diff --git a/dygraph/transforms/functional.py b/dygraph/transforms/functional.py
index c3f0265b0e1f4a250b41d5b86717b3d87797351d..24e755d16116f549563f70f7ef1eab9a8d613544 100644
--- a/dygraph/transforms/functional.py
+++ b/dygraph/transforms/functional.py
@@ -1,5 +1,4 @@
-# coding: utf8
-# Copyright (c) 2019 PaddlePaddle Authors. All Rights Reserve.
+# Copyright (c) 2020 PaddlePaddle Authors. All Rights Reserve.
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
diff --git a/dygraph/transforms/transforms.py b/dygraph/transforms/transforms.py
index 261b29781f59ca211f66b240937952b51af5949f..7a24089aaf8db3d5455031d26b57d52e09559322 100644
--- a/dygraph/transforms/transforms.py
+++ b/dygraph/transforms/transforms.py
@@ -1,5 +1,4 @@
-# coding: utf8
-# Copyright (c) 2019 PaddlePaddle Authors. All Rights Reserve.
+# Copyright (c) 2020 PaddlePaddle Authors. All Rights Reserve.
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
diff --git a/dygraph/utils/__init__.py b/dygraph/utils/__init__.py
index 9b6978c8a43e18cfe172f480b08092095752ccdb..cb5201d560bf6f5b55afe43ca07e29321c25f28c 100644
--- a/dygraph/utils/__init__.py
+++ b/dygraph/utils/__init__.py
@@ -1,5 +1,4 @@
-# coding: utf8
-# Copyright (c) 2019 PaddlePaddle Authors. All Rights Reserve.
+# Copyright (c) 2020 PaddlePaddle Authors. All Rights Reserve.
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
diff --git a/dygraph/utils/logging.py b/dygraph/utils/logging.py
index 6f0c25ff554cb80b9435e72ed47432d4bb6e6813..7657c4584fb7b3418e4570dd5584ec67943bf37b 100644
--- a/dygraph/utils/logging.py
+++ b/dygraph/utils/logging.py
@@ -1,5 +1,4 @@
-# coding: utf8
-# Copyright (c) 2019 PaddlePaddle Authors. All Rights Reserve.
+# Copyright (c) 2020 PaddlePaddle Authors. All Rights Reserve.
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
diff --git a/dygraph/utils/metrics.py b/dygraph/utils/metrics.py
index f7bab020ab44131f5d46643cf0522dd6acf483ee..8b1747e9b2586471018185849827cafc956a5353 100644
--- a/dygraph/utils/metrics.py
+++ b/dygraph/utils/metrics.py
@@ -1,5 +1,4 @@
-# coding: utf8
-# Copyright (c) 2019 PaddlePaddle Authors. All Rights Reserve.
+# Copyright (c) 2020 PaddlePaddle Authors. All Rights Reserve.
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
diff --git a/dygraph/utils/utils.py b/dygraph/utils/utils.py
index 435374aea27e57db16fee13522cb09d68d40fbec..e8b5a1586f20dab97442d34747a2b39cab005833 100644
--- a/dygraph/utils/utils.py
+++ b/dygraph/utils/utils.py
@@ -1,5 +1,4 @@
-# coding: utf8
-# Copyright (c) 2019 PaddlePaddle Authors. All Rights Reserve.
+# Copyright (c) 2020 PaddlePaddle Authors. All Rights Reserve.
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.