Sample doughnut chart

read "ef2019.csv"
select kanton == "Zürich"
project partei, fiktive_waehlende
select partei regexi "fdp|cvp|sp|svp|gps|glp"
format fiktive_waehlende "%02d"
delegate "doughnutchart -colors blue,orange,red,#080,#8B3,#BC3"