code: def onBars(self, bars):
      currentDateTime = bars.getDateTime()
  
      if self._shouldRebalance(currentDateTime):
          self.__rebalanceMonth = currentDateTime.month
          self._rebalance()
  
      self._placePendingOrders()
  
imports: from __future__ import print_function
  from pyalgotrade import strategy
  from pyalgotrade import plotter
  from pyalgotrade.barfeed import yahoofeed
  from pyalgotrade.technical import ma
  from pyalgotrade.technical import cumret
  from pyalgotrade.stratanalyzer import sharpe
  from pyalgotrade.stratanalyzer import returns
label_desc: Use image node_id 10 for calling the MarketTiming obj's underlying member method code with example usage: obj.onBars(bars) without return types