Original code by icostan here I added DST code. Warning may not be perfect yet. Could be a bug or two. It only supports 3 major sessions right now but you can add your own rules for the other timezones by copying my logic.
It is open source so please add the other sessions and regions as needed and update me please.
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.