Pomise 내부 탐색

[dudckd6744]

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https://velog.io/@elrion018/%EA%B0%84%EB%8B%A8%ED%95%9C-%ED%94%84%EB%A1%9C%EB%AF%B8%EC%8A%A4Promise-%EC%95%BD%EC%86%8D%EC%9D%84-%EC%A7%81%EC%A0%91-%EA%B5%AC%ED%98%84%ED%95%B4%EB%B3%B4%EC%9E%90