What is the bucket policy format ?

{
  "Version": "2008-10-17",
  "Id": "<textasId>",
  "Statement":
    {
       "Sid":"1",
       "Effect": "Allow",
       "Principal": {
          "AWS": "<AWS AccountNumber>"
        },
        "Action": ["s3:GetObject"],
        "Resource": "arn:aws:s3:::<Bucket Name>"
     }
}

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