BANK NIFTY: Weekly Demand and Supply Zones

Bank Nifty weekly chart is interesting. 20000-20460 was a supply zone but last week cendal managed to close above this supply zone. So now
*20000-20460 is now the demand zone on the weekly chart.

*If it will manage to hold this level then next resistance @ 21600 and major supply zone @ 23700-23900.