public IEnumerator TestListClassificationsModels()
        {
            Log.Debug("NaturalLanguageUnderstandingServiceV1IntegrationTests", "Attempting to TestListClassificationsModels...");
            ListClassificationsModelsResponse listClassificationsModelsResponse = null;

            service.ListClassificationsModels(
                callback: (DetailedResponse <ListClassificationsModelsResponse> response, IBMError error) =>
            {
                Log.Debug("NaturalLanguageUnderstandingServiceV1IntegrationTests", "ListClassificationsModelsResponse result: {0}", response.Response);
                listClassificationsModelsResponse = response.Result;
                Assert.IsNotNull(listClassificationsModelsResponse);
                Assert.IsNotNull(listClassificationsModelsResponse.Models);
                Assert.IsNull(error);
            }
                );

            while (listClassificationsModelsResponse == null)
            {
                yield return(null);
            }
            foreach (ClassificationsModelList classificationsModelList in listClassificationsModelsResponse.Models)
            {
                if (classificationsModelList.Models == null)
                {
                    continue;
                }
                foreach (ClassificationsModel classificationModel in classificationsModelList.Models)
                {
                    if (classificationModel.Name.Contains("testString") || classificationModel.Name.Contains("newString"))
                    {
                        DeleteModelResults deleteModelResults = null;
                        service.DeleteClassificationsModel(
                            callback: (DetailedResponse <DeleteModelResults> response, IBMError error) =>
                        {
                            Log.Debug("NaturalLanguageUnderstandingServiceV1IntegrationTests", "DeleteCategoriesModel result: {0}", response.Response);
                            deleteModelResults = response.Result;
                            Assert.IsNull(error);
                        },
                            modelId: classificationModel.ModelId
                            );

                        while (deleteModelResults == null)
                        {
                            yield return(null);
                        }
                    }
                }
            }
        }