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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 delete_topology_entry(self, **req):
 """Delete the entries from the topology DB. """

        session = db.get_session()
        with session.begin(subtransactions=True):
            try:
                rows = session.query(DfaTopologyDb).filter_by(**req).all()
            except orm_exc.NoResultFound:
                LOG.info("No Topology results found for %s", req)
                return
            try:
                for row in rows:
                    session.delete(row)
            except Exception as exc:
                LOG.error("Exception raised %s", str(exc))