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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def language(self, language_code=None):
 """ Set the language code to assign to objects retrieved using this QuerySet. """

        if language_code is None:
            language_code = appsettings.PARLER_LANGUAGES.get_default_language()

        self._language = language_code
        return self