logging Use lazy % formatting in logging functions

[605666069]

do_logging.py中
logging.info('n==%d' % n) 警告提示
应改为 logging.info('n==%d', n)

[pranavparvekar]

(The string is formatted lazily only if info level is active.)
logging.basicConfig(level=logging.INFO)
logging.info('n=%d', n)