docs: def get_feature_model():
      """Return the FeatureFlipper model defined in settings.py
      """
      try:
          return apps.get_model(flipper_settings.FEATURE_FLIPPER_MODEL)
      except ValueError:
          raise ImproperlyConfigured(
              "FEATURE_FLIPPER_MODEL must be of the form 'app_label.model_name'")
      except LookupError:
          raise ImproperlyConfigured(
              "FEATURE_FLIPPER_MODEL refers to model '{}' that has not been"
              " installed".format(flipper_settings.FEATURE_FLIPPER_MODEL))