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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 add_lb_nodes(self, lb_id, nodes):
 """ Adds nodes to an existing LBaaS instance :param string lb_id: Balancer id :param list nodes: Nodes to add. {address, port, [condition]} :rtype :class:`list` """

        log.info("Adding load balancer nodes %s" % nodes)
        resp, body = self._request(
                'post', 
                '/loadbalancers/%s/nodes' % lb_id,
                data={'nodes': nodes})
        return body