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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 maybe_download(url, work_directory):
 """Download the data from Marlin's website, unless it's already here."""

    filename = url.split("/")[-1]
    filepath = os.path.join(work_directory, filename)
    if not os.path.exists(filepath):
        logger.info("Downloading to {}...".format(filepath))
        download(url, work_directory)
    return filepath