private function createContainer($settings)
    {
        if (is_string($settings)) {
            return $this->createContainerFromString($settings);
        }

        if (is_array($settings)) {
            return $this->createContainerFromArray($settings);
        }

        throw new WrongServicesConfigurationException(
            sprintf('`services` must be either string or an array, but `%s` given.', gettype($settings))
        );
    }