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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 available_languages(self):
 """ Returns available languages. """

        from .models import Translation

        return (
            Translation.objects.filter(
                identifier=self.linguist_identifier, object_id=self.pk
            )
            .values_list("language", flat=True)
            .distinct()
            .order_by("language")
        )