def METHOD_NAME(self):
    rets = []
    for name, model in self.models.items():
        logger.debug(f"Starting time-step of sub-model: {name}")
        model.before()
        ret = model.solve()
        rets.append(ret)
        model.after()
        logger.debug(f"Finished time-step of sub-model: {name}")
    return rets