Multidate preset ?

hi,
it is possible to do something like that: {"velky_piatok":{{"mday":"19","mon":"4","year":"2019"},{"mday":"10","mon":"4","year":"2020"},{"mday":"2","mon":"4","year":"2021"},{"mday":"15","mon":"4","year":"2022"},{"mday":"7","mon":"4","year":"2023"}}}
If yes what is correct syntax ?

Or i must split it to multiple presets..each for one date ?

No idea how to add irregular holiday in one expression ?