unable to display relation data on map #458

I'm trying to display building:part tag on the map.

function relation_scan_function(relation) if relation:Find("type") == "multipolygon" or relation:Find("type") == "building" then relation:Accept() end end

`while true do
local rel = way:NextRelation()
if not rel then
break
end
-- print ("Part of route "..way:FindInRelation("ref"))
part = way:FindInRelation("building:part")
-- part = way:FindInRelation("ref")

    if part == "yes" then
        way:Layer("building",false)
        relation:Attribute("building:part",part)
    else
        way:Attribute("building:part","empty")
    end

end`

I have used above code for the same, if anyone implemented above code then help me to get the building:part tag data.