diff --git a/aleksis/apps/tezor/util/invoice.py b/aleksis/apps/tezor/util/invoice.py
index c1aa4e53ec3f4c165cf2124f0369136fd8edf704..0879b43ca33a25d655ab7aeec48251392f90b94c 100644
--- a/aleksis/apps/tezor/util/invoice.py
+++ b/aleksis/apps/tezor/util/invoice.py
@@ -1,5 +1,6 @@
 _provider_cache = {}
 
+
 def provider_factory(variant, payment=None):
     from djp_sepa.providers import DirectDebitProvider, PaymentPledgeProvider  # noqa
     from payments.paypal import PaypalProvider  # noqa