code: def pop_marker(self, reset):
          
  
          marker = self.markers.pop()
  
          if reset:
              # Make the values available to be read again
              marker.extend(self.look_ahead)
              self.look_ahead = marker
          elif self.markers:
              # Otherwise, reassign the values to the top marker
              self.markers[-1].extend(marker)
          else:
              # If there are not more markers in the stack then discard the values
              pass
docs: Pop a marker off of the marker stack. If reset is True then the
          iterator will be returned to the state it was in before the
          corresponding call to push_marker().