old_contents: # Copyright 2015-2016 NEC Corporation.  All rights reserved.
  #
  #    Licensed under the Apache License, Version 2.0 (the "License"); you may
  #    not use this file except in compliance with the License. You may obtain
  #    a copy of the License at
  #
  #         http://www.apache.org/licenses/LICENSE-2.0
  #
  #    Unless required by applicable law or agreed to in writing, software
  #    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
  #    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
  #    License for the specific language governing permissions and limitations
  #    under the License.
  
  from sqlalchemy.orm import exc as sa_exc
  
  from neutron.db import l3_db
  from oslo_log import log as logging
  
  LOG = logging.getLogger(__name__)
  
  
  def get_tenant_id_by_router(session, router_id):
      rt_tid = None
      with session.begin(subtransactions=True):
          try:
              router = session.query(l3_db.Router).filter_by(id=router_id).one()
              rt_tid = router.tenant_id
          except sa_exc.NoResultFound:
              LOG.debug("router not found %s", router_id)
  
      LOG.debug("rt_tid=%s", rt_tid)
      return rt_tid
  
new_contents: # Copyright 2015-2016 NEC Corporation.  All rights reserved.
  #
  #    Licensed under the Apache License, Version 2.0 (the "License"); you may
  #    not use this file except in compliance with the License. You may obtain
  #    a copy of the License at
  #
  #         http://www.apache.org/licenses/LICENSE-2.0
  #
  #    Unless required by applicable law or agreed to in writing, software
  #    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
  #    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
  #    License for the specific language governing permissions and limitations
  #    under the License.
  
  from sqlalchemy.orm import exc as sa_exc
  
  from neutron.db import l3_db
  from oslo_log import log as logging
  
  LOG = logging.getLogger(__name__)
  
  
  def get_tenant_id_by_router(session, router_id):
      with session.begin(subtransactions=True):
          try:
              router = session.query(l3_db.Router).filter_by(id=router_id).one()
              rt_tid = router.tenant_id
              LOG.debug("rt_tid=%s", rt_tid)
              return rt_tid
          except sa_exc.NoResultFound:
              LOG.debug("router not found %s", router_id)
  
subject: Move return to inside try