old_contents: #
  # Copyright 2014 Quantopian, Inc.
  #
  # 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.
  
  # Note that part of the API is implemented in TradingAlgorithm as
  # methods (e.g. order). These are added to this namespace via the
  # decorator `api_methods` inside of algorithm.py.
  
  import zipline
  from .finance import (commission, slippage)
  from .utils import math_utils
  
  from zipline.finance.slippage import (
      FixedSlippage,
      VolumeShareSlippage,
  )
  
  
  batch_transform = zipline.transforms.BatchTransform
  
  
  def symbol(symbol_str, as_of_date=None):
      """Default symbol lookup for any source that directly maps the
      symbol to the identifier (e.g. yahoo finance).
  
      Keyword argument as_of_date is ignored.
      """
      return symbol_str
  
  __all__ = [
      'slippage',
      'commission',
      'math_utils',
      'batch_transform',
      'FixedSlippage',
      'VolumeShareSlippage'
  ]
  
new_contents: #
  # Copyright 2014 Quantopian, Inc.
  #
  # 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.
  
  # Note that part of the API is implemented in TradingAlgorithm as
  # methods (e.g. order). These are added to this namespace via the
  # decorator `api_methods` inside of algorithm.py.
  
  import zipline
  from .finance import (commission, slippage)
  from .utils import math_utils
  
  from zipline.finance.slippage import (
      FixedSlippage,
      VolumeShareSlippage,
  )
  
  
  batch_transform = zipline.transforms.BatchTransform
  
  
  def symbol(symbol_str, as_of_date=None):
      """Default symbol lookup for any source that directly maps the
      symbol to the identifier (e.g. yahoo finance).
  
      Keyword argument as_of_date is ignored.
      """
      return symbol_str
  
  __all__ = [
      'symbol',
      'slippage',
      'commission',
      'math_utils',
      'batch_transform',
      'FixedSlippage',
      'VolumeShareSlippage'
  ]
  
subject: Add symbol to __all__