code: def _callbackPlaceFillOrders(self, d):
          
          if isinstance(d, FilledOrder):
              self.onOrderMatched(d)
          elif isinstance(d, Order):
              self.onOrderPlaced(d)
          elif isinstance(d, UpdateCallOrder):
              self.onUpdateCallOrder(d)
          else:
              pass
docs: This method distringuishes notifications caused by Matched orders
              from those caused by placed orders