Support for ITUNESALBUMADVISORY field

In relation to this tag Florian, could you also add support for ITUNESALBUMADVISORY
as well? this is linked to the iTunes/Apple Music API under collectionExplicitness

Is it also stored in the tags of the file or only available via Apple Music metadata? If it's in the tags, I'd need to know the atom id (or get my hands on an example file).

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Error. I use the track specific, ITUNESADVISORY,
without problems.