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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 deregister_instances(self, load_balancer_name, instances):
 """ Remove Instances from an existing Load Balancer. :type load_balancer_name: string :param load_balancer_name: The name of the Load Balancer :type instances: List of strings :param instances: The instance ID's of the EC2 instances to remove. :rtype: List of strings :return: An updated list of instances for this Load Balancer. """

        params = {'LoadBalancerName' : load_balancer_name}
        self.build_list_params(params, instances,
                               'Instances.member.%d.InstanceId')
        return self.get_list('DeregisterInstancesFromLoadBalancer',
                             params, [('member', InstanceInfo)])