Motivation: strategy(lookback) never worked for me and even if it did, it is garbage, because I want to set a date instead of number of bars. I can see on the chart clearly what period is irrelevant (in trading).
In true TradingView spirit, the author of this script has published it open-source, so traders can understand and verify it. Cheers to the author! You may use it for free, but reuse of this code in a publication is governed by House Rules. You can favorite it to use it on a chart.