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.
  
  from oslo_versionedobjects import base
  from oslo_versionedobjects import fields
  
  from os_vif import objects
  from os_vif.objects import base as osv_base
  
  
  @base.VersionedObjectRegistry.register
  class Network(osv_base.VersionedObject):
      """Represents a network."""
      # Version 1.0: Initial version
      VERSION = '1.0'
  
      fields = {
          'id': fields.UUIDField(),
          'bridge': fields.StringField(),
          'label': fields.StringField(),
          'subnets': fields.ObjectField('SubnetList'),
          'multi_host': fields.BooleanField(),
          'should_provide_bridge': fields.BooleanField(),
          'should_provide_vlan': fields.BooleanField(),
          'bridge_interface': fields.StringField(nullable=True),
          'vlan': fields.StringField(nullable=True),
      }
  
      obj_relationships = {
          'subnets': [
              ('1.0', '1.0'),
          ],
      }
  
      def __init__(self, **kwargs):
          kwargs.setdefault('subnets', objects.subnet.SubnetList(objects=[]))
          kwargs.setdefault('multi_host', False)
          kwargs.setdefault('should_provide_bridge', False)
          kwargs.setdefault('should_provide_vlan', False)
          super(Network, self).__init__(**kwargs)
  
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.
  
  from oslo_versionedobjects import base
  from oslo_versionedobjects import fields
  
  from os_vif import objects
  from os_vif.objects import base as osv_base
  
  
  @base.VersionedObjectRegistry.register
  class Network(osv_base.VersionedObject):
      """Represents a network."""
      # Version 1.0: Initial version
      VERSION = '1.0'
  
      fields = {
          'id': fields.UUIDField(),
          'bridge': fields.StringField(),
          'label': fields.StringField(),
          'subnets': fields.ObjectField('SubnetList'),
          'multi_host': fields.BooleanField(),
          'should_provide_bridge': fields.BooleanField(),
          'should_provide_vlan': fields.BooleanField(),
          'bridge_interface': fields.StringField(nullable=True),
          'vlan': fields.StringField(nullable=True),
      }
  
      def __init__(self, **kwargs):
          kwargs.setdefault('subnets', objects.subnet.SubnetList(objects=[]))
          kwargs.setdefault('multi_host', False)
          kwargs.setdefault('should_provide_bridge', False)
          kwargs.setdefault('should_provide_vlan', False)
          super(Network, self).__init__(**kwargs)
  
subject: Remove obsolete obj_relationships attribute