How to get Value from multiple row variable set ServiceNow?

var mrvsParsed = JSON.parse(current.variables.internal_name_of_mrvs.toString());

for(var x in mrvsParsed){

var system = mrvsParsed[x].system;

var role = mrvsParsed[x].role;

gs.info("system = " + system + "     " + "role = " + role);

}