class_docstr: A volume share slippage model as defined in Zipline's VolumeShareSlippage model.
  The slippage is calculated by multiplying the price impact constant by the square of the ratio of the order
  to the total volume.
  
  Check https://www.quantopian.com/help#ide-slippage for more details.
  
  :param priceImpact: Defines how large of an impact your order will have on the backtester's price calculation.
  :type priceImpact: float.
code: def __init__(self, priceImpact=0.1):
      super(VolumeShareSlippage, self).__init__()
      self.__priceImpact = priceImpact
  
file_path: pyalgotrade/pyalgotrade/broker/slippage.py
imports: import abc
  import six
label_desc: Use image node_id 1 to create a new VolumeShareSlippage object from inherited base classes: SlippageModel with example: obj = VolumeShareSlippage(priceImpact)