def s3_downloader(bucketName, key, localPath)
    # (1) Create S3 object
    s3 = Aws::S3::Resource.new(region: 'ap-southeast-2')
    # (2) Create the source object
    sourceObj = s3.bucket(bucketName).object(key)
    # (3) Download the file
    sourceObj.get(response_target: localPath)
    puts "s3://#{bucketName}/#{key} has been downloaded to #{localPath}"
end