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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 auto_slug(self):
 """This property is used to auto-generate a slug from the name attribute. It can be customized by subclasses. """

        slug = self.name
        if slug is not None:
            slug = slugify(slug, separator=self.SLUG_SEPARATOR)
            session = sa.orm.object_session(self)
            if not session:
                return None
            query = session.query(Entity.slug).filter(
                Entity._entity_type == self.object_type
            )
            if self.id is not None:
                query = query.filter(Entity.id != self.id)
            slug_re = re.compile(re.escape(slug) + r"-?(-\d+)?")
            results = [
                int(m.group(1) or 0)  # 0: for the unnumbered slug
                for m in (slug_re.match(s.slug) for s in query.all() if s.slug)
                if m
            ]

            max_id = max(-1, -1, *results) + 1
            if max_id:
                slug = f"{slug}-{max_id}"
        return slug