locale.py 文件源码

def check_available_translations(self, locale):
        """
        Test a locale for having a translation available
        locale -- string with standard language code, locale code, or name
        """
        if not self.localedir:
            return None
        #Note that this isn't a typo for self.language; self.languages
        #is cached so we don't have to query the file system every
        #time this function is called.
        if not hasattr(self, 'languages'):
            self.languages = self.get_available_translations()

        if not locale:
            return None

        if locale[:5] in self.languages:
            return locale[:5]
        #US English is the outlier, all other English locales want real English:
        if locale[:2] == 'en' and locale[:5] != 'en_US':
            return 'en_GB'
        if locale[:2] in self.languages:
            return locale[:2]
        return None