old_contents: #
  #    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.
  
  # If you update this list, please also update
  # doc/source/features.rst.
  SUPPORTED_API_EXTENSIONS = [
      'agent',
      'quotas',
      'extra_dhcp_opt',
      'binding',
      'dhcp_agent_scheduler',
      'security-group',
      'external-net',
      'router',
      'l3_agent_scheduler',
      'subnet_allocation',
      'port-security',
      'allowed-address-pairs',
      'net-mtu',
      'default-subnetpools',
      'extraroute',
  ]
  
new_contents: #
  #    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.
  
  # If you update this list, please also update
  # doc/source/features.rst.
  SUPPORTED_API_EXTENSIONS = [
      'agent',
      'quotas',
      'extra_dhcp_opt',
      'binding',
      'dhcp_agent_scheduler',
      'security-group',
      'external-net',
      'router',
      'l3_agent_scheduler',
      'subnet_allocation',
      'port-security',
      'allowed-address-pairs',
      'net-mtu',
      'default-subnetpools',
      'extraroute',
      'bgp',
      'trunk',
      'flow_classifier',
      'sfc',
  ]
  
subject: Add bgp, trunk, flow_classifier, and sfc to supported API extensions