diff --git a/erpnext/manufacturing/doctype/production_order/production_order.py b/erpnext/manufacturing/doctype/production_order/production_order.py
index 2f2c40ef2d4..b5abb733b01 100644
--- a/erpnext/manufacturing/doctype/production_order/production_order.py
+++ b/erpnext/manufacturing/doctype/production_order/production_order.py
@@ -18,6 +18,7 @@ from erpnext.stock.stock_balance import get_planned_qty, update_bin_qty
 from frappe.utils.csvutils import getlink
 from erpnext.stock.utils import get_bin, validate_warehouse_company, get_latest_stock_qty
 from erpnext.utilities.transaction_base import validate_uom_is_integer
+from six import text_type
 
 class OverProductionError(frappe.ValidationError): pass
 class StockOverProductionError(frappe.ValidationError): pass
@@ -591,10 +592,10 @@ def make_timesheet(production_order, company):
 
 @frappe.whitelist()
 def add_timesheet_detail(timesheet, args):
-	if isinstance(timesheet, unicode):
+	if isinstance(timesheet, text_type):
 		timesheet = frappe.get_doc('Timesheet', timesheet)
 
-	if isinstance(args, unicode):
+	if isinstance(args, text_type):
 		args = json.loads(args)
 
 	timesheet.append('time_logs', args)