The use of the Compliance settings on a bucket (a feature used to achieve bucket immutability or WORM-style storage) allow you to make sure that no files are modified or deleted ahead of a certain time.
Enable Compliance mode on the bucket by going to 'Bucket Settings > Compliance'. Note for this example, I have set the retention time to be only (1) day. You may set this value to be in days/weeks/months/years, but you cannot set in hours.

Next, copy your files up to that bucket.
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If you attempt to delete a file within the bucket you will receive the following error until after the (1) day retention period is up:
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