diff --git a/src/yunohost/data_migrations/0021_migrate_to_bullseye.py b/src/yunohost/data_migrations/0021_migrate_to_bullseye.py
index 58bb259f7..eace6ca2e 100644
--- a/src/yunohost/data_migrations/0021_migrate_to_bullseye.py
+++ b/src/yunohost/data_migrations/0021_migrate_to_bullseye.py
@@ -87,8 +87,8 @@ class MyMigration(Migration):
         # and the code inside /usr/bin/deb-systemd-invoke to see how it calls /usr/sbin/policy-rc.d ...
         # and also invoke-rc.d ...
         write_to_file(
-            '/usr/sbin/policy-rc.d',
-            '#!/bin/bash\n[[ "$1" =~ "nginx" ]] && [[ "$2" == "restart" ]] && exit 101 || exit 0'
+            "/usr/sbin/policy-rc.d",
+            '#!/bin/bash\n[[ "$1" =~ "nginx" ]] && [[ "$2" == "restart" ]] && exit 101 || exit 0',
         )
         os.system("chmod +x /usr/sbin/policy-rc.d")
 
@@ -260,7 +260,6 @@ class MyMigration(Migration):
                 raw_msg=True,
             )
 
-
         postupgradecmds = f"apt-mark auto {' '.join(basephp74packages_to_install)}\n"
         postupgradecmds += "rm -f /usr/sbin/policy-rc.d\n"
         postupgradecmds += "echo 'Restarting nginx...' >&2\n"
diff --git a/src/yunohost/tools.py b/src/yunohost/tools.py
index 1eaad28bf..dbd3af5f5 100644
--- a/src/yunohost/tools.py
+++ b/src/yunohost/tools.py
@@ -448,7 +448,12 @@ def _list_upgradable_apps():
 
 @is_unit_operation()
 def tools_upgrade(
-    operation_logger, target=None, apps=False, system=False, allow_yunohost_upgrade=True, postupgradecmds=""
+    operation_logger,
+    target=None,
+    apps=False,
+    system=False,
+    allow_yunohost_upgrade=True,
+    postupgradecmds="",
 ):
     """
     Update apps & package cache, then display changelog