Or you could eliminate all this automatic stuff by handing it to someons sitting at a window with the following short instructions:

If dark = 1 then turniton 'now night
if dark = 0 then turnitoff 'now day

This would also help with the unemployment problem, but probably not with sales.


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Oh dear, I am sorry, I just couldn't resist.
Yeah, I know, some people are just no bloody help at all, are they?
I'm just gonna go sit in the corner for a while