def METHOD_NAME(self, stage: str = RunningStage.TRAINING) -> float:
    """Return the time elapsed for a particular stage (in seconds)"""
    start = self.start_time(stage)
    end = self.end_time(stage)
    offset = self._offset if stage == RunningStage.TRAINING else 0
    if start is None:
        return offset
    if end is None:
        return time.monotonic() - start + offset
    return end - start + offset