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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 delay_off(self):
 """ The `timer` trigger will periodically change the LED brightness between 0 and the current brightness setting. The `off` time can be specified via `delay_off` attribute in milliseconds. """


        # Workaround for ev3dev/ev3dev#225.
        # 'delay_on' and 'delay_off' attributes are created when trigger is set
        # to 'timer', and destroyed when it is set to anything else.
        # This means the file cache may become outdated, and we may have to
        # reopen the file.
        for retry in (True, False):
            try:
                self._delay_off, value = self.get_attr_int(self._delay_off, 'delay_off')
                return value
            except OSError:
                if retry:
                    self._delay_off = None
                else:
                    raise