docs: def classify_collection(self, classifier_id, collection, **kwargs):
          """
          Classify multiple phrases.
  
          Returns label information for multiple phrases. The status must be `Available`
          before you can use the classifier to classify text.
          Note that classifying Japanese texts is a beta feature.
  
          :param str classifier_id: Classifier ID to use.
          :param list[ClassifyInput] collection: The submitted phrases.
          :param dict headers: A `dict` containing the request headers
          :return: A `DetailedResponse` containing the result, headers and HTTP status code.
          :rtype: DetailedResponse
          """
  
          if classifier_id is None:
              raise ValueError('classifier_id must be provided')
          if collection is None:
              raise ValueError('collection must be provided')
          collection = [self._convert_model(x, ClassifyInput) for x in collection]
  
          headers = {}
          if 'headers' in kwargs:
              headers.update(kwargs.get('headers'))
          sdk_headers = get_sdk_headers('natural_language_classifier', 'V1',
                                        'classify_collection')
          headers.update(sdk_headers)
  
          data = {'collection': collection}
  
          url = '/v1/classifiers/{0}/classify_collection'.format(
              *self._encode_path_vars(classifier_id))
          response = self.request(
              method='POST',
              url=url,
              headers=headers,
              json=data,
              accept_json=True)
          return response