@classmethod<EOL><INDENT>def callbacks(cls, eventType=None):<DEDENT>
key = '<STR_LIT>'.format(cls.__name__)<EOL>try:<EOL><INDENT>callbacks = getattr(cls, key)<EOL><DEDENT>except AttributeError:<EOL><INDENT>callbacks = {}<EOL>setattr(cls, key, callbacks)<EOL><DEDENT>return callbacks.get(eventType, []) if eventType is not None else callbacks<EOL>
Returns a list of callback methods that can be invoked whenever an event is processed.

:return: {subclass of <Event>: <list>, ..}