add license

pgl/utils/log_writer.py

+# Copyright (c) 2020 PaddlePaddle Authors. All Rights Reserved
+#
+# 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.
 """ log writer setup
 """
-
 import sys
 
 LogWriter = None
@@ -8,7 +20,6 @@ LogWriter = None
 if int(sys.version[0]) == 3:
     from visualdl import LogWriter
     LogWriter = LogWriter
-
 else:
     from tensorboardX import SummaryWriter
     LogWriter = SummaryWriter