Find a translation with given language

        :param key: Language to find
        :type key: text_type
        :rtype: [CtsTextMetadata]
        :returns: List of availables translations

def get_translation_in(self, key=None):
        """ Find a translation with given language

        :param key: Language to find
        :type key: text_type
        :rtype: [CtsTextMetadata]
        :returns: List of availables translations
        """
        if key is not None:
            return [
                item
                for item in self.texts.values()
                if isinstance(item, CtsTranslationMetadata) and item.lang == key
                ]
        else:
            return [
                item
                for item in self.texts.values()
                if isinstance(item, CtsTranslationMetadata)
            ]