code: def __getstate__(self):
      return (self.__dateTime, self.__price, self.__amount)
  
imports: from pyalgotrade import barfeed
  from pyalgotrade import bar
  from pyalgotrade.barfeed import csvfeed
  from pyalgotrade.utils import dt
  import datetime
label_desc: Use image node_id 3 for calling the TradeBar obj's underlying member method code with example usage: obj.__getstate__() and returns: self,  self,  self