def calculate_lookback(self):
        if self.lookback_hours == 0:
            lookback_start = None
            lookback_end = None
        else:
            delta_hours = timedelta(hours=self.lookback_hours)
            lookback_start = datetime.now() - delta_hours
            lookback_start = lookback_start.strftime('%Y%m%d%H')
            if self.lookback_window == 0:
                lookback_end = None
            else:
                delta_window = timedelta(hours=self.lookback_window)
                lookback_end = datetime.now() - delta_hours + delta_window
                lookback_end = lookback_end.strftime('%Y%m%d%H')
        self.logger.debug('lookback_start: %s' % lookback_start)
        self.logger.debug('lookback_end: %s' % lookback_end)
        return (lookback_start, lookback_end)
dataset/ETHPy150Open notmyname/slogging/slogging/log_common.py/LogProcessorCommon.calculate_lookback/original