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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def s3_list(s3_bucket, s3_access_key_id, s3_secret_key, prefix=None):
 """ Lists the contents of the S3 bucket that end in .tbz and match the passed prefix, if any. """

    bucket = s3_connect(s3_bucket, s3_access_key_id, s3_secret_key)
    return sorted([key.name for key in bucket.list()
                   if key.name.endswith(".tbz")
                   and (prefix is None or key.name.startswith(prefix))])