问如何从TradingView上的价目表中获取最高和最低的价格？

EN

//@version=5
indicator("visible high/low", overlay = true)

start_time = chart.left_visible_bar_time
end_time = chart.right_visible_bar_time

in_visible_range = time >= start_time and time <= end_time

var float hh = na
var float ll = na

if in_visible_range
    if na(hh)
        hh := high
        ll := low
    else
        hh := math.max(hh, high)
        ll := math.min(ll, low)

if time == end_time
    label.new(x = bar_index, y = high, text = "High : " + str.tostring(hh) + "\nLow : " + str.tostring(ll), style = label.style_label_lower_right)
    line.new(x1 = bar_index - 1, y1 = hh, x2 = bar_index, y2 = hh, extend = extend.both)
    line.new(x1 = bar_index - 1, y1 = ll, x2 = bar_index, y2 = ll, extend = extend.both)```