How to can i use :isA loop? i really need the answer

guys how can i use :isA in for loops please explain

Uhh.. By doing :IsA()...? Loops dont change arguments....

for name,inst in pairs(workspace:GetChildren()) do
	if inst:IsA("BasePart") then --Define className in the IsA to check if an instance "IsA" Classname.
		inst.BrickColor = BrickColor.Random()
	end
end