Update authorization_control.py
diff --git a/erpnext/setup/doctype/authorization_control/authorization_control.py b/erpnext/setup/doctype/authorization_control/authorization_control.py
index fa708b5..be97964 100644
--- a/erpnext/setup/doctype/authorization_control/authorization_control.py
+++ b/erpnext/setup/doctype/authorization_control/authorization_control.py
@@ -40,7 +40,7 @@
 		chk = 1
 		add_cond1,add_cond2	= '',''
 		if based_on == 'Itemwise Discount':
-			add_cond1 += " and master_name = '"+cstr(item.replace("'", "\'"))+"'"
+			add_cond1 += " and master_name = '"+cstr(item).replace("'", "\'")+"'"
 			itemwise_exists = frappe.db.sql("""select value from `tabAuthorization Rule`
 				where transaction = %s and value <= %s
 				and based_on = %s and company = %s and docstatus != 2 %s %s""" %