'Add one or more nodes to cluster'

def add_nodes(self, cluster_name, num_nodes, aliases=None, no_create=False, image_id=None, instance_type=None, zone=None, placement_group=None, spot_bid=None):

    cl = self.get_cluster(cluster_name)
    return cl.add_nodes(num_nodes, aliases=aliases, image_id=image_id, instance_type=instance_type, zone=zone, placement_group=placement_group, spot_bid=spot_bid, no_create=no_create)
