def UpdateClass(self, class_name, gtfs_class):
    if class_name not in self._class_mapping:
      raise problems.NonexistentMapping(class_name)
    self._class_mapping[class_name] = gtfs_class
This method will subscribe a callback function to an event name.
dataset/ETHPy150Open google/transitfeed/transitfeed/gtfsfactory.py/GtfsFactory.UpdateClass--crossover with--dataset/ETHPy150Open joerussbowman/gaeutilities/appengine_utilities/event.py/Event.subscribe