Subgroups in a group, how to create them?

Hi all

Is it possible to greate a group into a group (subgroup)?
So that if you select e.g. a room from a group, that within this selection you have another group?


Here is a quote from the official documentation. They also include the examples you seek.

The Group is a special Item type that can be used to define a category or collection into which you can combine other Items or Groups. An Item may be put into one or more groups, and groups may be nested inside other groups.