import frappe


@frappe.whitelist()
def filt_itemby_supplier(doctype, txt, searchfield, start, page_len, filters):
    return frappe.db.sql("""Select parent from `tabItem Supplier` where  supplier= %s""",(filters.get("supplier"))); 

@frappe.whitelist()
def filteritem(doctype, txt, searchfield, start, page_len, filters):
    return frappe.db.sql("""select item_code, item_name, item_group, volume, item_type,stock_uom from `tabItem`"""); 
[((17, 35), 'frappe.whitelist', 'frappe.whitelist', ([], {}), '()\n', (33, 35), False, 'import frappe\n'), ((235, 253), 'frappe.whitelist', 'frappe.whitelist', ([], {}), '()\n', (251, 253), False, 'import frappe\n'), ((334, 444), 'frappe.db.sql', 'frappe.db.sql', (['"""select item_code, item_name, item_group, volume, item_type,stock_uom from `tabItem`"""'], {}), "(\n    'select item_code, item_name, item_group, volume, item_type,stock_uom from `tabItem`'\n    )\n", (347, 444), False, 'import frappe\n')]