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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 raid_alert(self, status, used, available, type):
 """RAID alert messages. [available/used] means that ideally the array may have _available_ devices however, _used_ devices are in use. Obviously when used >= available then things are good. """

        if type == 'raid0':
            return 'OK'
        if status == 'inactive':
            return 'CRITICAL'
        if used is None or available is None:
            return 'DEFAULT'
        elif used < available:
            return 'WARNING'
        return 'OK'