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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 remove(self):
 """Permanently remove a specific object version from the database. .. warning:: This by-passes the normal versioning and should only be used when you want to permanently delete a specific object version. Otherwise use :py:data:`ObjectVersion.delete()`. Note the method does not remove the associated file instance which must be garbage collected. :returns: ``self``. """

        with db.session.begin_nested():
            if self.file_id:
                self.bucket.size -= self.file.size
            self.query.filter_by(
                bucket_id=self.bucket_id,
                key=self.key,
                version_id=self.version_id,
            ).delete()

        return self