How do I get number of segments in day/dusk/night?

[TobyKenobi]

In uiclock.lua I found data.day, which holds the number of segments in the day phase.

But I can't work out how to access it. I've tried code like this:

local function myfunction(inst,data)
	myday=data.day
end

but data is nul, so I assume I'm not referencing it right, or it's unavailable to mods.

So can anyone help me get the number of segments in each phase please?