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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 compute_file_hashes(file_path, hashes=frozenset(['md5'])):
 """ Digests data read from file denoted by file_path. """

    if not os.path.exists(file_path):
        logging.warning("%s does not exist" % file_path)
        return
    else:
        logging.debug("Computing [%s] hashes for file [%s]" % (','.join(hashes), file_path))

    try:
        with open(file_path, 'rb') as fd:
            return compute_hashes(fd, hashes)
    except (IOError, OSError) as e:
        logging.warning("Error while calculating digest(s) for file %s: %s" % (file_path, str(e)))
        raise