diff --git a/docs/conf.py b/docs/conf.py
index 372ff5e94..914126684 100644
--- a/docs/conf.py
+++ b/docs/conf.py
@@ -11,6 +11,8 @@
 # add these directories to sys.path here. If the directory is relative to the
 # documentation root, use os.path.abspath to make it absolute, like shown here.
 #
+from __future__ import annotations
+
 import os
 import sys
 from pathlib import Path
diff --git a/payments/__init__.py b/payments/__init__.py
index 3ca8e04d9..89c7fdb48 100644
--- a/payments/__init__.py
+++ b/payments/__init__.py
@@ -89,8 +89,8 @@ def get_payment_model():
     payment_model = apps.get_model(app_label, model_name)
     if payment_model is None:
         msg = (
-            'PAYMENT_MODEL refers to model "%s" that has not been installed'
-            % settings.PAYMENT_MODEL
+            f'PAYMENT_MODEL refers to model "{settings.PAYMENT_MODEL}"'
+            " that has not been installed"
         )
         raise ImproperlyConfigured(msg)
     return payment_model
diff --git a/payments/coinbase/test_coinbase.py b/payments/coinbase/test_coinbase.py
index 200c191ec..387fc60da 100644
--- a/payments/coinbase/test_coinbase.py
+++ b/payments/coinbase/test_coinbase.py
@@ -95,7 +95,7 @@ def test_incorrect_data_process_data(self):
     def test_provider_returns_checkout_url(self, mocked_post, mocked_time):
         code = "123abc"
         signature = "21d476eff7b2e6cccdfe6deb0c097ba638d5de7e775b303e4fdb2f8bfeff72e2"
-        url = "https://sandbox.coinbase.com/checkouts/%s" % code
+        url = f"https://sandbox.coinbase.com/checkouts/{code}"
         post = MagicMock()
         post.json = MagicMock(return_value={"button": {"code": code}})
         post.status_code = 200
diff --git a/payments/sofort/__init__.py b/payments/sofort/__init__.py
index 1d1d65101..8c9b42478 100644
--- a/payments/sofort/__init__.py
+++ b/payments/sofort/__init__.py
@@ -122,7 +122,7 @@ def refund(self, payment, amount=None):
                 "holder": sender_data["holder"],
                 "bic": sender_data["bic"],
                 "iban": sender_data["iban"],
-                "title": "Refund %s" % payment.description,
+                "title": f"Refund {payment.description}",
                 "transaction_id": payment.transaction_id,
                 "amount": amount,
                 "comment": "User requested a refund",
diff --git a/testapp/manage.py b/testapp/manage.py
index 4c28ac632..6f0326023 100755
--- a/testapp/manage.py
+++ b/testapp/manage.py
@@ -1,5 +1,6 @@
 #!/usr/bin/env python
 """Django's command-line utility for administrative tasks."""
+
 from __future__ import annotations
 
 import os