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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 reboot_instances(self, instance_ids=None):
 """ Reboot the specified instances. :type instance_ids: list :param instance_ids: The instances to terminate and reboot """

        params = {}
        if instance_ids:
            self.build_list_params(params, instance_ids, 'InstanceId')
        return self.get_status('RebootInstances', params)