Quarry Active turtle script

local timer_reset=5 --time in seconds between checking for activity
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local active=false
local run=true
os.startTimer(timer_reset)
while run do
    local event=os.pullEvent()
    if event == "turtle_inventory" then         -- if something is messing with the inventory
        active=true             -- the miner is active
    elseif event == "timer" then            -- if the timer has timed out
        if active then              -- if it has done something since last timer
            os.startTimer(timer_reset)  -- start a new timer
            active=false            -- reset boolean
        else                    -- otherwise
            rs.setOutput("top",true)    -- output redstone on top face
            run=false           -- stop running
        end
    end
end