diff --git a/bookwyrm/templatetags/shelf_tags.py b/bookwyrm/templatetags/shelf_tags.py
index 7aef638f4..6c4f59c36 100644
--- a/bookwyrm/templatetags/shelf_tags.py
+++ b/bookwyrm/templatetags/shelf_tags.py
@@ -36,22 +36,19 @@ def get_next_shelf(current_shelf):
 def active_shelf(context, book):
     """check what shelf a user has a book on, if any"""
     user = context["request"].user
-    return (
-        cache.get_or_set(
-            f"active_shelf-{user.id}-{book.id}",
-            lambda u, b: (
-                models.ShelfBook.objects.filter(
-                    shelf__user=u,
-                    book__parent_work__editions=b,
-                ).first()
-                or False
-            ),
-            user,
-            book,
-            timeout=15552000,
-        )
-        or {"book": book}
-    )
+    return cache.get_or_set(
+        f"active_shelf-{user.id}-{book.id}",
+        lambda u, b: (
+            models.ShelfBook.objects.filter(
+                shelf__user=u,
+                book__parent_work__editions=b,
+            ).first()
+            or False
+        ),
+        user,
+        book,
+        timeout=15552000,
+    ) or {"book": book}
 
 
 @register.simple_tag(takes_context=False)
diff --git a/bookwyrm/tests/models/test_fields.py b/bookwyrm/tests/models/test_fields.py
index 935a62632..5bb7fecc6 100644
--- a/bookwyrm/tests/models/test_fields.py
+++ b/bookwyrm/tests/models/test_fields.py
@@ -430,7 +430,7 @@ class ModelFields(TestCase):
         output = instance.field_to_activity(user.avatar)
         self.assertIsNotNone(
             re.match(
-                fr"https:\/\/{DOMAIN}\/.*\.jpg",
+                rf"https:\/\/{DOMAIN}\/.*\.jpg",
                 output.url,
             )
         )
diff --git a/requirements.txt b/requirements.txt
index 534a0593d..ad000d505 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -20,7 +20,7 @@ django-storages==1.11.1
 django-redis==5.2.0
 
 # Dev
-black==21.4b0
+black==21.4b2
 pytest-django==4.1.0
 pytest==6.1.2
 pytest-cov==2.10.1