def METHOD_NAME(self):
    text = ''
    for topo_id in self.args.topo_dicts:
        net = self.args.networks['tester_%s' % topo_id.file_fmt()][0]
        ipv = 'ipv4'
        if ipv not in net:
            ipv = 'ipv6'
        ip = net[ipv]
        text += str(topo_id) + ' ' + str(ip) + '\n'
        pathlib.Path(self.args.output_dir, 'sig-testing.conf').write_text(text)