How do I use math.randomseed(tick()) within a function or is that unnecessary?

Answers on a previous question told me to put math.randomseed(tick()) told me to put that line of code at the very top of my script. My question is do I need it in a function or can I put it at Line One?

math.randomseed(tick())-- does it have to be here
local Maps = game.ServerStorage:WaitForChild("Maps"):GetChildren()

function chooseMap()
	--math.randomseed(tick()) or can it/ does it have to be here
	local randomMap = Maps[math.random(1, #Maps)]:Clone()
	print(randomMap.Name)
end

what if i had a while true do loop like this :

--does math.randomseed(tick()) have to be on the first line
-- code in between and naming functions and stuff before the loop, etc.
while true do
	function chooseMap() -- or can it be in the function
end

basically, my question is where can it go

You put it inside the function

	local Maps = game.ServerStorage:WaitForChild("Maps"):GetChildren()
	function chooseMap()
	    math.randomseed(tick()) --< RIGHT HERE
	    local randomMap = Maps[math.random(1, #Maps)]:Clone()
	    print(randomMap.Name)
	end