code: def pushLast(self):
      if self.__grouper is not None:
          self.appendWithDateTime(
              self.__grouper.getDateTime(), self.__grouper.getGrouped()
          )
          self.__grouper = None
          self.__range = None
  
imports: import abc
  import six
  from pyalgotrade import dataseries
  from pyalgotrade.dataseries import bards
  from pyalgotrade import bar
  from pyalgotrade import resamplebase
label_desc: Use image node_id 4 for calling the DSResampler obj's underlying member method code with example usage: obj.pushLast() without return types