diff --git a/npbackup/gui/main.py b/npbackup/gui/main.py
index 1813a23..22a3d4b 100644
--- a/npbackup/gui/main.py
+++ b/npbackup/gui/main.py
@@ -46,7 +46,7 @@ THREAD_SHARED_DICT = {}
 
 def _about_gui(version_string: str, config_dict: dict) -> None:
     license_content = LICENSE_TEXT
-    
+
     result = check_new_version(config_dict)
     if result:
         new_version = [
diff --git a/npbackup/upgrade_client/upgrader.py b/npbackup/upgrade_client/upgrader.py
index 999abe9..7e7b058 100644
--- a/npbackup/upgrade_client/upgrader.py
+++ b/npbackup/upgrade_client/upgrader.py
@@ -181,7 +181,9 @@ def auto_upgrader(
     platform_and_arch = "{}/{}".format(get_os(), os_arch()).lower()
 
     try:
-        host_id = "{}/{}/{}".format(auto_upgrade_host_identity, installed_version, group)
+        host_id = "{}/{}/{}".format(
+            auto_upgrade_host_identity, installed_version, group
+        )
         id_record = "{}/{}".format(platform_and_arch, host_id)
     except TypeError:
         id_record = platform_and_arch
diff --git a/upgrade_server/upgrade_server/crud.py b/upgrade_server/upgrade_server/crud.py
index 48eaaf1..dbc2ed7 100644
--- a/upgrade_server/upgrade_server/crud.py
+++ b/upgrade_server/upgrade_server/crud.py
@@ -51,7 +51,7 @@ def get_current_version() -> Optional[CurrentVersion]:
     try:
         path = os.path.join(config_dict["upgrades"]["data_root"], "VERSION")
         if os.path.isfile(path):
-            with open(path, "r", encoding='utf-8') as fh:
+            with open(path, "r", encoding="utf-8") as fh:
                 ver = fh.readline()
                 return CurrentVersion(version=ver)
     except OSError: