string模块中包含了一个很有用的Template类，可以先写好字符串模板，后期使用的时候直接替换就可以了。
1 >>>from string importTemplate 2 >>> t =Template(‘${village}folk send $$10 to $cause.‘) 3 >>> t.substitute(village=‘Nottingham‘, cause=‘the ditch fund‘) 4 ‘Nottinghamfolk send $10 to the ditch fund.‘
>>> t =Template(‘Return the $item to $owner.‘) >>> d = dict(item=‘unladen swallow‘) >>> t.substitute(d) Traceback(most recent call last): ... KeyError:‘owner‘ >>> t.safe_substitute(d) ‘Return the unladen swallow to $owner.‘
1 >>> import time, os.path 2 >>> photofiles = [‘img_1074.jpg‘, ‘img_1076.jpg‘, ‘img_1077.jpg‘] 3 >>> class BatchRename(Template): 4 ... delimiter = ‘%‘ 5 >>> fmt = raw_input(‘Enter rename style (%d-date %n-seqnum %f-format): ‘) 6 Enter rename style (%d-date %n-seqnum %f-format): Ashley_%n%f 7 8 >>> t = BatchRename(fmt) 9 >>> date = time.strftime(‘%d%b%y‘) 10 >>> for i, filename in enumerate(photofiles): 11 ... base, ext = os.path.splitext(filename) 12 ... newname = t.substitute(d=date, n=i, f=ext) 13 ... print ‘{0} --> {1}‘.format(filename, newname) 14 15 img_1074.jpg --> Ashley_0.jpg 16 img_1076.jpg --> Ashley_1.jpg 17 img_1077.jpg --> Ashley_2.jpg
原文：http://www.cnblogs.com/fireflow/p/4864902.html