'List balanced network interfaces for a load balancer.
:param  load_balancer: The load balancer you wish to update.
:type:  load_balancer: :class:`ProfitBricksLoadBalancer`
:return:    ``list`` of class ``ProfitBricksNetorkInterface``
:rtype:     `list`'

def ex_list_load_balanced_nics(self, load_balancer):

    action = load_balancer.extra['entities']['balancednics']['href']
    response = self.connection.request(action=action, params={'depth': 3}, method='GET', with_full_url=True)
    return self._to_interfaces(response.object)
