'Adds server\'s IP address to load balancer
:param lb_id: Load balancer ID
:rtype: ``str``
:param server_ips: Array of server IP IDs
:rtype: ``list`` of ``str``
:return: Instance of load balancer
:rtype: ``dict``'

def ex_add_servers_to_load_balancer(self, lb_id, server_ips=[]):

    body = {'server_ips': server_ips}
    response = self.connection.request(action=('load_balancers/%s/server_ips' % lb_id), data=body, method='POST')
    return response.object
