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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 _get_translation(self, field, code):
 """ Gets the translation of a specific field for a specific language code. This raises ObjectDoesNotExist if the lookup was unsuccesful. As of today, this stuff is cached. As the cache is rather aggressive it might cause rather strange effects. However, we would see the same effects when an ordinary object is changed which is already in memory: the old state would remain. """


        if not code in self._translation_cache:
            translations = self.translations.select_related()

            logger.debug(
                u'Matched with field %s for language %s. Attempting lookup.',
                field, code
            )

            try:
                translation_obj = translations.get(language_code=code)

            except ObjectDoesNotExist:
                translation_obj = None

            self._translation_cache[code] = translation_obj

            logger.debug(u'Translation not found in cache.')

        else:
            logger.debug(u'Translation found in cache.')
            # Get the translation from the cache
            translation_obj = self._translation_cache.get(code)

        # If this is none, it means that a translation does not exist
        # It is important to cache this one as well
        if not translation_obj:
            raise ObjectDoesNotExist

        field_value = getattr(translation_obj, field)

        logger.debug(
            u'Found translation object %s, returning value %s.',
            translation_obj, field_value
        )

        return field_value