old_contents: # -*- coding: utf-8 -*-
  
  
  class BarObject(object):
      def __init__(self):
          self.open = 0.0
          self.close = 0.0
          self.high = 0.0
          self.low = 0.0
          self.volume = 0.0
          self.last = 0.0
          self.acc_net_value = 0.0
          self.unit_net_value = 0.0
          self.discount_rate = 0.0
          self.total_turnover = 0.0
          self.settlement = 0.0
          self.prev_settlement = 0.0
          self.open_interest = 0.0
          self.basis_spread = 0.0
          self.datetime = None
  
      @property
      def instrument(self):
          pass
  
      @property
      def order_book_id(self):
          pass
  
      @property
      def symbol(self):
          pass
  
      @property
      def is_trading(self):
          pass
  
      def mavg(self, intervals, frequency="day"):
          """
          Returns moving average price for the given security for a give number
              of intervals for a frequency, by default to `"day"`.
          :param int intervals: a given number of intervals, e.g. given number
              of days
          :param str frequency: frequency of the give number of intervals, by
              default as ‘day’.
          """
          pass
  
      def vwap(self, intervals, frequency="day"):
          pass
  
      def history(self, bar_count, frequency, field):
          pass
  
      def __repr__(self):
          return "BarObject({0})".format(self.__dict__)
  
      def __getitem__(self, key):
          return self.__dict__[key]
  
  
  class BarMap(object):
      def __init__(self, dt, data_proxy):
          self.dt = dt
          self.data_proxy = data_proxy
  
      def update_dt(self, dt):
          self.dt = dt
  
      def __getitem__(self, key):
          return self.data_proxy.get_data(key, self.dt)
  
      def __repr__(self):
          return "{0}()".format(type(self).__name__)
  
new_contents: # -*- coding: utf-8 -*-
  
  
  class BarObject(object):
      def __init__(self):
          self.open = 0.0
          self.close = 0.0
          self.high = 0.0
          self.low = 0.0
          self.volume = 0.0
          self.last = 0.0
          self.acc_net_value = 0.0
          self.unit_net_value = 0.0
          self.discount_rate = 0.0
          self.total_turnover = 0.0
          self.settlement = 0.0
          self.prev_settlement = 0.0
          self.open_interest = 0.0
          self.basis_spread = 0.0
          self.datetime = None
  
      @property
      def instrument(self):
          raise NotImplementedError
  
      @property
      def order_book_id(self):
          raise NotImplementedError
  
      @property
      def symbol(self):
          raise NotImplementedError
  
      @property
      def is_trading(self):
          raise NotImplementedError
  
      def mavg(self, intervals, frequency="day"):
          """
          Returns moving average price for the given security for a give number
              of intervals for a frequency, by default to `"day"`.
          :param int intervals: a given number of intervals, e.g. given number
              of days
          :param str frequency: frequency of the give number of intervals, by
              default as ‘day’.
          """
          raise NotImplementedError
  
      def vwap(self, intervals, frequency="day"):
          raise NotImplementedError
  
      def history(self, bar_count, frequency, field):
          raise NotImplementedError
  
      def __repr__(self):
          return "BarObject({0})".format(self.__dict__)
  
      def __getitem__(self, key):
          return self.__dict__[key]
  
  
  class BarMap(object):
      def __init__(self, dt, data_proxy):
          self.dt = dt
          self.data_proxy = data_proxy
  
      def update_dt(self, dt):
          self.dt = dt
  
      def __getitem__(self, key):
          return self.data_proxy.get_data(key, self.dt)
  
      def __repr__(self):
          return "{0}()".format(type(self).__name__)
  
subject: replace pass with raise NotImplementedError