old_contents: # Copyright (c) 2017 One Convergence Inc
  # 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 networking_sfc.extensions import sfc
  from neutron_lib.api import converters as lib_converters
  from neutron_lib.api import extensions
  from neutron_lib import exceptions as neutron_exc
  
  
  DEFAULT_TAP_ENABLED = False
  TAP_EXT = "networking-sfc-tap"
  
  
  class MultiplePortPairsInTapPPGNotSupported(neutron_exc.InvalidInput):
      """Multiple Port Pairs in Tap PPG not allowed"""
      message = _("Multiple port pairs in Tap port-pair-group is not allowed.")
  
  
  class ConsecutiveTapPPGNotSupported(neutron_exc.InvalidInput):
      """Unsupported Tap deployment"""
      message = _("Consecutive Tap PPG in port-chain is not supported now.")
  
  
  EXTENDED_ATTRIBUTES_2_0 = {
      'port_pair_groups': {
          'tap_enabled': {
              'allow_post': True, 'allow_put': False,
              'is_visible': True, 'default': DEFAULT_TAP_ENABLED,
              'convert_to': lib_converters.convert_to_boolean
          }
      }
  }
  
  
  class Tap(extensions.ExtensionDescriptor):
  
      @classmethod
      def get_name(cls):
          return "Networking SFC Passive Tap Service Function support"
  
      @classmethod
      def get_alias(cls):
          return TAP_EXT
  
      @classmethod
      def get_description(cls):
          return "Extension for Passive TAP Service Function support"
  
      @classmethod
      def get_updated(cls):
          return "2017-10-20T10:00:00-00:00"
  
      def get_extended_resources(self, version):
          if version == "2.0":
              return EXTENDED_ATTRIBUTES_2_0
          else:
              return {}
  
      @classmethod
      def get_plugin_interface(cls):
          return sfc.SfcPluginBase
  
new_contents: # Copyright (c) 2017 One Convergence Inc
  # 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 networking_sfc.extensions import sfc
  from neutron_lib.api import converters as lib_converters
  from neutron_lib.api import extensions
  from neutron_lib import exceptions as neutron_exc
  
  from networking_sfc._i18n import _
  
  DEFAULT_TAP_ENABLED = False
  TAP_EXT = "networking-sfc-tap"
  
  
  class MultiplePortPairsInTapPPGNotSupported(neutron_exc.InvalidInput):
      """Multiple Port Pairs in Tap PPG not allowed"""
      message = _("Multiple port pairs in Tap port-pair-group is not allowed.")
  
  
  class ConsecutiveTapPPGNotSupported(neutron_exc.InvalidInput):
      """Unsupported Tap deployment"""
      message = _("Consecutive Tap PPG in port-chain is not supported now.")
  
  
  EXTENDED_ATTRIBUTES_2_0 = {
      'port_pair_groups': {
          'tap_enabled': {
              'allow_post': True, 'allow_put': False,
              'is_visible': True, 'default': DEFAULT_TAP_ENABLED,
              'convert_to': lib_converters.convert_to_boolean
          }
      }
  }
  
  
  class Tap(extensions.ExtensionDescriptor):
  
      @classmethod
      def get_name(cls):
          return "Networking SFC Passive Tap Service Function support"
  
      @classmethod
      def get_alias(cls):
          return TAP_EXT
  
      @classmethod
      def get_description(cls):
          return "Extension for Passive TAP Service Function support"
  
      @classmethod
      def get_updated(cls):
          return "2017-10-20T10:00:00-00:00"
  
      def get_extended_resources(self, version):
          if version == "2.0":
              return EXTENDED_ATTRIBUTES_2_0
          else:
              return {}
  
      @classmethod
      def get_plugin_interface(cls):
          return sfc.SfcPluginBase
  
subject: Use i18n from the project