- roots = (("http%s://%s:%d/" %
- ('s' if f['service_ssl_flag'] else '',
- f['service_host'],
- f['service_port']))
- for f in keep_services)
+ roots = ("{}://[{}]:{:d}/".format(
+ 'https' if ks['service_ssl_flag'] else 'http',
+ ks['service_host'],
+ ks['service_port'])
+ for ks in keep_services)