The file path in S3 will always has the following format:
http://{bucket-name}.s3.amazonaws.com/<path_to_file>
Now, ff you are given a link to a file inside of s3 in the following format:
s3://my-bucket/test-folder/dir1/test-file.txt
You should be able to convert it to the following url:
http://my-bucket.s3.amazonaws.com/test-folder/dir1/test-file.txt
So, you can now easily convert s3 protocol to http protocol, which allows you to download using your favourite browser, or simply use wget command to download file from S3 bucket.
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