get Internal id of Item

To get the internal id of item using function,

  function getItemInternalIdByDisplayName(itemDisplayName) {
        try {
            let itemSearchObj = search.create({
                type: search.Type.ITEM,
                filters: [
                    ['isinactive', 'is', 'F'],                        // Only active items
                    'AND',
                    ['name', 'is', itemDisplayName]
                ],
                columns: ['internalid']
            });
            let searchResult = itemSearchObj.run().getRange({
                start: 0,
                end: 1
            });
            if (searchResult && searchResult.length > 0) {
                let internalId = searchResult[0].getValue({
                    name: 'internalid'
                });
                return internalId;
            } else {
                return null;                                          // Item not found
            }

        } catch (err) {
            log.error("error@getItemInternalIdByDisplayName", err);
            return false;
        }
    }