new_contents: # 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 neutron_lib._i18n import _
  from neutron_lib import exceptions
  
  
  class AddressGroupNotFound(exceptions.NotFound):
      message = _("Address group %(address_group_id)s could not be found.")
  
  
  class AddressesNotFound(exceptions.NotFound):
      message = _("Addresses %(addresses)s not found in the address group "
                  "%(address_group_id)s.")
  
  
  class AddressesAlreadyExist(exceptions.BadRequest):
      message = _("Addresses %(addresses)s already exist in the "
                  "address group %(address_group_id)s.")
  
subject: Add address group exceptions