Using for loops in Data definition builder

Hello,

Using Data definition builder I'm trying to Display the dates in a certain combination and it's working when i tried using for loop it is throwing an error.

This is my input form. For each services i'm entering Data range and venue and trying displaying it.

This is my code:

def cube3=operation.application.getCube("OEP_FS");Dimension periodDim1=operation.application.getDimension("Services",cube3);def test1=periodDim1.getEvaluatedMembers("ILvl0Descendants(All Services)",cube3);
println(test1.toString());

def startdate
def enddate
Cube cube = operation.application.getCube("OEP_FS")
for(int i = 0;i<test1.size();i++){
DataGridDefinitionBuilder builder1 = cube.dataGridDefinitionBuilder()
builder1.addPov(['Entity', 'Years', 'Scenario', 'Version', 'Currency', 'Product','Plan Element','Custom 1','Period'],