public function preSave() {
parent::preSave();
// In case the skill languages is not know to the system, install them.
$languages = \Drupal::languageManager()
->getLanguages();
if (!isset($languages[$this->language_from])) {
$language = ConfigurableLanguage::createFromLangcode($this->language_from);
$language
->save();
}
if (!isset($languages[$this->language_to])) {
$language = ConfigurableLanguage::createFromLangcode($this->language_to);
$language
->save();
}
}