getTranslation and getParsedResult missing in version 17 #7

Hi,
I really enjoy your library and use it in all of my angular projects that are multi language. Today I upgraded to the new version 17 and now i have the problem, that my custom pipe to get a single translated value of a specified language by key doesn't work anymore. The code used is:

return this.ts.getTranslation(iso).pipe(map(translations => {
        return this.ts.getParsedResult(translations, key, interpolateParams);
}));

Field this.ts is my custom service extending TranslateService. Unfortunately getTranslation doesn't exist anymore and getParsedResult only takes two parameters now (passing translations is not supported anymore apparently). Searched all documentation for a replacement, but couldn't find anything. Could you guide me how to do this in version 17? Thanks in advance!