Does anyone have succeeded to create Matrix Parent and Child Item by script?

Recently, I have tried to create Matrix Parent Item.

First of all, set values on 'itemid', 'displayname' fields and set 'matrixtype' field as 'PARENT'.
For mandatory fields, set 'cogsaccount', 'assetaccount', 'taxschedule' fields with suitable values.
After defining the Item's options part, tried to submit parent record using nlapiSubmitRecord function.

But the Execution Log shows such result.

UNEXPECTED_ERROR: null

Is there a way around this?

Thanks,
Xiaoxin


Here is the code snippet.
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function suitelet(request, response){
var recMatrixParent = nlapiCreateRecord('inventoryitem');

recMatrixParent.setFieldValue('itemid', 'Matrix Parent');
recMatrixParent.setFieldValue('displayname', 'Matrix Parent');