Return object with episode number attached to episode.

def get_object(self, queryset=None):
        """Return object with episode number attached to episode."""
        if settings.PODCAST_SINGULAR:
            show = get_object_or_404(Show, id=settings.PODCAST_ID)
        else:
            show = get_object_or_404(Show, slug=self.kwargs['show_slug'])
        obj = get_object_or_404(Episode, show=show, slug=self.kwargs['slug'])
        index = Episode.objects.is_public_or_secret().filter(show=show, pub_date__lt=obj.pub_date).count()
        obj.index = index + 1
        obj.index_next = obj.index + 1
        obj.index_previous = obj.index - 1
        return obj