def subscribe(self, event, callback, args = None):
        if not {"event": event, "callback": callback, "args": args, } \
            in self.events:
            self.events.append({"event": event, "callback": callback, \
                "args": args, })
        return True
Ensures the title is used in the lilypond code.
dataset/ETHPy150Open joerussbowman/gaeutilities/appengine_utilities/event.py/Event.subscribe--crossover with--dataset/ETHPy150Open ntoll/foox/test/test_lilypond.py/TestLilypond.test_render_with_title