//@version=2
study(title = "Directional Flow Analyzer Indicator Heikin Ashi", shorttitle="Directional Flow Candles", overlay=true)

len=input(10)
o=ema(open,len)
c=ema(close,len)
h=ema(high,len)
l=ema(low,len)

haclose = (o+h+l+c)/4
haopen = na(haopen[1]) ? (o + c)/2 : (haopen[1] + haclose[1]) / 2
hahigh = max (h, max(haopen,haclose))
halow = min (l, min(haopen,haclose))

len2=input(10)
o2=ema(haopen, len2)
c2=ema(haclose, len2)
h2=ema(hahigh, len2)
l2=ema(halow, len2)

col=o2>c2 ? red : lime
plotcandle(o2, h2, l2, c2, title="heikin smoothed", color=col)

Please help me to update this pine script from version 2 to the latest version 5 or 6