'Resolves the resource\'s attributes.
Heat extension: "InstanceList" returns comma delimited list of server
ip addresses.'

def _resolve_attribute(self, name):

    if (name == self.INSTANCE_LIST):
        return (u','.join(((inst.FnGetAtt('PublicIp') or '0.0.0.0') for inst in grouputils.get_members(self))) or None)
