def setUp(self):
     apt_pkg.Config.set("Dir::State::lists","./test-data/var/lib/apt/lists.cl")
     apt_pkg.Config.set("Dir::State::status","./test-data/var/lib/dpkg/status")
     apt_pkg.Config.set("Dir::Etc::SourceList","./test-data/etc/apt/sources.list.cl")
     apt_pkg.Config.set("Dir::Etc::SourceParts","x")
     logging.info("updating the cache")
     localeinfo = LocaleInfo("languagelist", "..")
     self.lang_cache = LanguageSelectorPkgCache(
         localeinfo, apt.progress.base.OpProgress())
     self.lang_cache.update()
     self.lang_cache.open()