function to return names and/or ips of instances connected to an aws ELB

aws_elb_info.py

def get_elb_member_info(load_balancers):
    """ Takes an ELB (Elastic Load balancer) name or list of ELB namess and
        returns a dict of:

        ips: a list containing the private ip address of each instance
        names: a list containing the tag_Name of each instancee
    """
    import boto

    elbs = boto.connect_elb().get_all_load_balancers(load_balancers)
    instance_infos = []
    for elb in elbs:
        instance_infos += elb.instances
    reservations = boto.connect_ec2().get_all_instances(
        instance_ids=[instance.id for instance in instance_infos])
    instance_names = [i.tags['Name'] for r in reservations
                      for i in r.instances]
    instance_ips = [i.private_ip_address for r in reservations
                    for i in r.instances]
    return {"names": instance_names, "ips": instance_ips}