import frappe
from frappe.model.document import Document

class ItemWizard(Document):
	pass


@frappe.whitelist()
def get_item_group_filter_data(item_group):
	doctype = "Item Group"
	doc = frappe.get_doc(doctype, item_group)

	data = {
		"brand": [item.brand for item in doc.brand]
	}

	return data

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var item_group

frappe.ui.form.on("Item Wizard", {
  // refresh: function(frm) {

  // }
	item_group: function (frm) {

		frappe.call({
			method:"ss_custom_erpnext.ss_custom_erpnext.doctype.item_wizard.item_wizard.get_item_group_filter_data",
			args: {item_group:frm.doc.item_group},
			async: false,
			callback: function(r) {
				item_group = r.message
			}
		});


		frm.set_query("brand", function () {
		return {
			filters: {
			name: ["in", item_group.brand],
			},
		};
		});
	},
});