Feature Idea: Song "groups" in Playlist

Had this idea for a while… basically, sometimes, I will add two songs to a playlist which occur next to one another on an album. One might be the interlude/elongated intro for the other, for example, which means they flow together very smoothly.

Then I will add both songs to a playlist which I intend to shuffle and, far more likely than not, those songs will be separated in the resulting queue.

I propose a feature here that no other streaming service has yet, to my knowledge: song groups. (feel free to change the name)

Through some kind of mechanism, a user can group songs together as a single unit in a playlist or queue, such that shuffling them will never make them occur “detached” from one another. They always get moved together, unless the user wants to actively decouple them.