flowchart TB
    n1([開始])
    n2([結束])
    n3[&amp;&#35;39;\n        獲取掃描持續時間（秒）\n\n        Returns:\n ...]
    n4[return int&#40;time.time&#40;&#41; - self._start_...]
    n1 --> n3
    n3 --> n4
    n4 --> n2