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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 _scale_down(self, instances, count):
 """Return a list of |count| last created instances by launch time. :param instances: A list of instances. :type instances: list :param count: Number of instances to scale down. :type count: integer :return: List of instances to be scaled down. :rtype: list """

        i = sorted(instances, key=lambda i: i.launch_time, reverse=True)
        if not i:
            return []
        running = len(i)
        logger.info('%d instance/s are running.', running)
        logger.info('Scaling down %d instances of those.', count)
        if count > running:
            logger.info('Scale-down value is > than running instance/s - using maximum of %d!', running)
            count = running
        return i[:count]