new_contents: # Copyright 2020 NOKIA
  #
  #    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.
  
  import mock
  import testtools
  
  from nuage_neutron.plugins.common.base_plugin import RootNuagePlugin
  from nuage_neutron.plugins.common.service_plugins.port_attributes \
      import nuage_redirect_target
  from nuage_neutron.vsdclient import restproxy
  
  
  class TestNuageRedirectTarget(testtools.TestCase):
  
      @mock.patch.object(RootNuagePlugin, 'init_vsd_client')
      @mock.patch.object(nuage_redirect_target.NuageRedirectTarget,
                         'core_plugin')
      def test_create_pg_for_rt(self, *_):
          driver = nuage_redirect_target.NuageRedirectTarget()
          fake_sg = {
              'security_group_rules': []
          }
          driver.core_plugin.get_security_group = mock.MagicMock(
              return_value=fake_sg)
          vsdclient_mock = mock.MagicMock()
          driver.vsdclient = vsdclient_mock
          vsdclient_mock.create_security_group_using_parent.side_effect = (
              restproxy.RESTProxyError(
                  vsd_code=restproxy.REST_PG_EXISTS_ERR_CODE))
          rt = {'parentID': '1', 'parentType': 'l2domain'}
          pg = driver._create_pg_for_rt(mock.MagicMock(), mock.MagicMock(),
                                        rt, mock.MagicMock())
          self.assertIsNotNone(pg)
          vsdclient_mock.create_security_group_rules.assert_not_called()
          vsdclient_mock.get_nuage_l2domain_policy_groups.assert_called()
  
subject: Add unittest for concurrent redirect target create