diff --git a/erpnext/controllers/item_variant.py b/erpnext/controllers/item_variant.py
index c2b50f4..24726ad 100644
--- a/erpnext/controllers/item_variant.py
+++ b/erpnext/controllers/item_variant.py
@@ -178,7 +178,7 @@
 @frappe.whitelist()
 def enqueue_multiple_variant_creation(item, args):
 	# There can be innumerable attribute combinations, enqueue
-	if isinstance(args, frappe.string_types):
+	if isinstance(args, string_types):
 		variants = json.loads(args)
 	total_variants = 1
 	for key in variants: