Need buy/sell signal arrows in the chart for the below afl codes

The afl you gave worked properly but i still need buy/sell codes for the signals generated .

Below is the afl 

var1 = (Ref(close,-2) > Ref(close,-1)) and (ref(volume,-2) > Ref(volume,-1)) and (volume > Ref(volume,-2));

filter = var1;
AddColumn(close, "close",1.2);
AddColumn(var1,"var1",1.2);

In the above afl  you have not defined Buy or sell  at all, Please check where you what buy or sell to be initiated like example

Buy = var1;

etc.,

I just want that green and red signals in the charts when put that afl code … Can I know how do I do that .?