def ex_set_balancer_policies_backend_server(self, name, instance_port,
                                                policies):
        params = {
            'Action': 'SetLoadBalancerPoliciesForBackendServer',
            'LoadBalancerName': name,
            'InstancePort': str(instance_port)
        }

        if policies:
            params = self._create_list_params(params, policies,
                                              'PolicyNames.member.%d')

        response = self.connection.request(ROOT, params=params)
        return response.status == httplib.OK
Replaces the current set of policies associated with a port on
dataset/ETHPy150Open apache/libcloud/libcloud/loadbalancer/drivers/elb.py/ElasticLBDriver.ex_set_balancer_policies_backend_server