sensor

function wrap(side)
    if peripheral.getType(side) == "sensor" then
        return peripheral.wrap(side)
    else
        return nil, "not a sensor"
    end
end

function call(side, ...)
    if peripheral.getType(side) == "sensor" then
        return peripheral.call(side, ...)
    else
        return nil, "not a sensor"
    end
end