old_contents: #
  # Copyright 2016 The BigDL Authors.
  #
  # 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.
  #
  __all__ = ["Trainer", "TorchNano", "InferenceOptimizer"]
  
  
  # unset the KMP_INIT_AT_FORK
  # which will cause significant slow down in multiprocessing training
  import os
  os.unsetenv('KMP_INIT_AT_FORK')
  from bigdl.nano.pytorch.inference import InferenceOptimizer
  from bigdl.nano.pytorch.trainer import Trainer
  from bigdl.nano.pytorch.torch_nano import TorchNano
  
new_contents: #
  # Copyright 2016 The BigDL Authors.
  #
  # 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.
  #
  __all__ = ["Trainer", "TorchNano", "InferenceOptimizer"]
  
  
  # unset the KMP_INIT_AT_FORK
  # which will cause significant slow down in multiprocessing training
  import os
  if 'KMP_INIT_AT_FORK' in os.environ:
      del os.environ['KMP_INIT_AT_FORK']
  from bigdl.nano.pytorch.inference import InferenceOptimizer
  from bigdl.nano.pytorch.trainer import Trainer
  from bigdl.nano.pytorch.torch_nano import TorchNano
  
subject: fix nano pytorch on windows (#5106)