diff --git a/erpnext/accounts/doctype/dunning/dunning.py b/erpnext/accounts/doctype/dunning/dunning.py
index ec116f3..81ec408 100644
--- a/erpnext/accounts/doctype/dunning/dunning.py
+++ b/erpnext/accounts/doctype/dunning/dunning.py
@@ -16,7 +16,6 @@
 import json
 
 import frappe
-
 from frappe import _
 from frappe.utils import getdate
 
diff --git a/erpnext/accounts/doctype/dunning/test_dunning.py b/erpnext/accounts/doctype/dunning/test_dunning.py
index 956b1cf..499a03b 100644
--- a/erpnext/accounts/doctype/dunning/test_dunning.py
+++ b/erpnext/accounts/doctype/dunning/test_dunning.py
@@ -6,11 +6,13 @@
 import frappe
 from frappe.utils import add_days, nowdate, today
 
-from erpnext.accounts.doctype.sales_invoice.sales_invoice import create_dunning as create_dunning_from_sales_invoice
 from erpnext.accounts.doctype.payment_entry.test_payment_entry import get_payment_entry
 from erpnext.accounts.doctype.purchase_invoice.test_purchase_invoice import (
 	unlink_payment_on_cancel_of_invoice,
 )
+from erpnext.accounts.doctype.sales_invoice.sales_invoice import (
+	create_dunning as create_dunning_from_sales_invoice,
+)
 from erpnext.accounts.doctype.sales_invoice.test_sales_invoice import (
 	create_sales_invoice_against_cost_center,
 )
diff --git a/erpnext/accounts/doctype/overdue_payment/overdue_payment.py b/erpnext/accounts/doctype/overdue_payment/overdue_payment.py
index e3820d7..6a543ad 100644
--- a/erpnext/accounts/doctype/overdue_payment/overdue_payment.py
+++ b/erpnext/accounts/doctype/overdue_payment/overdue_payment.py
@@ -4,5 +4,6 @@
 # import frappe
 from frappe.model.document import Document
 
+
 class OverduePayment(Document):
 	pass