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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 _update_usage_for_nlb(self, conn, nlb_arn, nlb_name):
 """ Update usage for a single NLB. :param conn: elbv2 API connection :type conn: :py:class:`ElasticLoadBalancing.Client` :param nlb_arn: Load Balancer ARN :type nlb_arn: str :param nlb_name: Load Balancer Name :type nlb_name: str """

        logger.debug('Updating usage for NLB %s', nlb_arn)
        listeners = paginate_dict(
            conn.describe_listeners,
            LoadBalancerArn=nlb_arn,
            alc_marker_path=['NextMarker'],
            alc_data_path=['Listeners'],
            alc_marker_param='Marker'
        )['Listeners']
        self.limits[
            'Listeners per network load balancer']._add_current_usage(
            len(listeners),
            aws_type='AWS::ElasticLoadBalancingV2::NetworkLoadBalancer',
            resource_id=nlb_name
        )