python过滤字符串中不属于指定集合中字符的类实例

本文实例讲述了python过滤字符串中不属于指定集合中字符的类。分享给大家供大家参考。具体如下：

# -*- coding: utf-8 -*-import setsclass Keeper(object):  def __init__(self, keep):    self.keep = sets.Set(map(ord, keep))  def __getitem__(self, n):    if n not in self.keep:      return None    return unichr(n)  def __call__(self, s):    return s.translate(self)makefilter = Keeperif __name__ == '__main__':  just_vowels = makefilter('aeiouy')  print just_vowels(u'four score and seven years ago')  # 输出: ouoeaeeyeaao  print just_vowels(u'tiger, tiger burning bright')  # 输出: ieieuii

希望本文所述对大家的Python程序设计有所帮助。