How can I buy songs/music video on the new AppleTV (4th Generation)

In the older model, I had access to iTunes and could purchase songs and music videos directly. Now it seems I can only rent/buy movies or tv shows through iTunes. The music app does not give me the option to buy any songs but rather sign up for Apple's streaming service which I do not want to do. Does anyone know if they'll be adding the iTunes music app back on to the new AppleTV? Thank you!