protected function getDefaultLibraries($magentoEdition)
    {

        // query whether or not, default libraries for the passed edition are available
        if (isset($this->defaultLibraries[$edition = strtolower($magentoEdition)])) {
            return $this->defaultLibraries[$edition];
        }

        // throw an exception, if the passed edition is not supported
        throw new \Exception(
            sprintf(
                'Default libraries for Magento \'%s\' not supported (MUST be one of CE or EE)',
                $magentoEdition
            )
        );
    }