how to address all tracks at once in M4L (chains//instrument rack//Live 9)

Hello everybody,

I'm building a very simple patch in M4L which should be able to change the values of ALL chain selectors of the Instrument Racks at once.
I simply don't manage to get it to work.
Is there any other command than "tracks 0" etc, something like "alltracks" or something similar?

Thanks a lot in advance!

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