このエラーメッセージに関する原因と対処に関して説明します。
エラーメッセージ(英語)：
s3 access denied on public bucket
対処
関連リンク
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https://aws.amazon.com/jp/premiumsupport/knowledge-center/s3-troubleshoot-403/
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https://aws.amazon.com/premiumsupport/knowledge-center/s3-access-denied-bucket-policy/
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https://aws.amazon.com/premiumsupport/knowledge-center/s3-access-denied-error/
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https://stackoverflow.com/questions/53346275/amazon-s3-bucket-policy-public-access-denied
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https://havecamerawilltravel.com/photographer/how-allow-public-access-amazon-bucket/
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https://www.directdefense.com/how-to-prevent-exploitation-of-amazon-s3-buckets-with-weak-permissions・・・