[minor] sales register report fixes
diff --git a/erpnext/accounts/report/sales_register/sales_register.py b/erpnext/accounts/report/sales_register/sales_register.py
index 4dc8f8c..1ef17ac 100644
--- a/erpnext/accounts/report/sales_register/sales_register.py
+++ b/erpnext/accounts/report/sales_register/sales_register.py
@@ -7,7 +7,7 @@
 from frappe import msgprint, _
 
 def execute(filters=None):
-	if not filters: filters = {}
+	if not filters: filters = frappe._dict({})
 
 	invoice_list = get_invoices(filters)
 	columns, income_accounts, tax_accounts = get_columns(invoice_list)