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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 record_used(kind, hash):
 """ Indicates a cachefile with the name 'hash' of a particular kind has been used so it will note be deleted on the next purge. :param str kind: The kind of cachefile. One of 'cache', 'seeds', or 'evs' :param str hash: The hash for the call descriptor, expected value descriptor, or counter seed. :rtype: None """

    if os.path.exists(LOG_FILEPATH):
        log = open(os.path.join(ROOT, 'used'), 'a')
    else:
        log = open(os.path.join(ROOT, 'used'), 'w+')

    log.writelines(["%s...%s\n" % (kind, hash)])