如何检查Python unicode字符串是否包含非西方字母？

如何检查Python unicode字符串是否包含非西方字母？

import unipredata as udlatin_letters= {}def is_latin(uchr):    try: return latin_letters[uchr]    except KeyError:         return latin_letters.setdefault(uchr, 'LATIN' in ud.name(uchr))def only_roman_chars(unistr):    return all(is_latin(uchr)for uchr in unistrif uchr.isalpha()) # isalpha suggested by John Machin>>> only_roman_chars(u"ελληνικά means greek")False>>> only_roman_chars(u"frappé")True>>> only_roman_chars(u"hôtel lœwe")True>>> only_roman_chars(u"123 ångstrom ð áß")True>>> only_roman_chars(u"russian: гага")False