diff --git a/aqt/installer.py b/aqt/installer.py
index 5d8efdd6..bfd09a64 100644
--- a/aqt/installer.py
+++ b/aqt/installer.py
@@ -749,7 +749,9 @@ def _set_install_qt_parser(self, install_qt_parser, *, is_legacy: bool):
 
     def _set_install_tool_parser(self, install_tool_parser, *, is_legacy: bool):
         install_tool_parser.set_defaults(func=self.run_install_tool, is_legacy=is_legacy)
-        install_tool_parser.add_argument("host", choices=["linux", "linux_arm64", "mac", "windows", "windows_arm64"], help="host os name")
+        install_tool_parser.add_argument(
+            "host", choices=["linux", "linux_arm64", "mac", "windows", "windows_arm64"], help="host os name"
+        )
         if not is_legacy:
             install_tool_parser.add_argument(
                 "target",
@@ -806,7 +808,9 @@ def make_parser_sde(cmd: str, desc: str, is_legacy: bool, action, is_add_kde: bo
 
         def make_parser_list_sde(cmd: str, desc: str, cmd_type: str):
             parser = subparsers.add_parser(cmd, description=desc)
-            parser.add_argument("host", choices=["linux", "linux_arm64", "mac", "windows", "windows_arm64"], help="host os name")
+            parser.add_argument(
+                "host", choices=["linux", "linux_arm64", "mac", "windows", "windows_arm64"], help="host os name"
+            )
             parser.add_argument(
                 "qt_version_spec",
                 metavar="(VERSION | SPECIFICATION)",
@@ -854,7 +858,9 @@ def _make_list_qt_parser(self, subparsers: argparse._SubParsersAction):
             "$ aqt list-qt mac desktop --archives 5.9.0 clang_64              # list archives in base Qt installation\n"
             "$ aqt list-qt mac desktop --archives 5.14.0 clang_64 debug_info  # list archives in debug_info module\n",
         )
-        list_parser.add_argument("host", choices=["linux", "linux_arm64", "mac", "windows", "windows_arm64"], help="host os name")
+        list_parser.add_argument(
+            "host", choices=["linux", "linux_arm64", "mac", "windows", "windows_arm64"], help="host os name"
+        )
         list_parser.add_argument(
             "target",
             nargs="?",
@@ -938,7 +944,9 @@ def _make_list_tool_parser(self, subparsers: argparse._SubParsersAction):
             "$ aqt list-tool mac desktop tools_ifw --long  # print tool variant names with metadata for QtIFW\n"
             "$ aqt list-tool mac desktop ifw --long        # print tool variant names with metadata for QtIFW\n",
         )
-        list_parser.add_argument("host", choices=["linux", "linux_arm64", "mac", "windows", "windows_arm64"], help="host os name")
+        list_parser.add_argument(
+            "host", choices=["linux", "linux_arm64", "mac", "windows", "windows_arm64"], help="host os name"
+        )
         list_parser.add_argument(
             "target",
             nargs="?",
@@ -1025,7 +1033,9 @@ def _set_common_arguments(self, subparser, *, is_legacy: bool, is_target_depreca
         """
         if is_legacy:
             subparser.add_argument("qt_version", help='Qt version in the format of "5.X.Y"')
-        subparser.add_argument("host", choices=["linux", "linux_arm64", "mac", "windows", "windows_arm64"], help="host os name")
+        subparser.add_argument(
+            "host", choices=["linux", "linux_arm64", "mac", "windows", "windows_arm64"], help="host os name"
+        )
         if is_target_deprecated:
             subparser.add_argument(
                 "target",
diff --git a/aqt/metadata.py b/aqt/metadata.py
index 391c8882..2d488ccb 100644
--- a/aqt/metadata.py
+++ b/aqt/metadata.py
@@ -234,7 +234,11 @@ def is_tools(self) -> bool:
     def to_url(self) -> str:
         return "online/qtsdkrepository/{os}{arch}/{target}/".format(
             os=self.host,
-            arch=("_x86" if self.host == "windows" else ("" if self.host in ("linux_arm64", "all_os", "windows_arm64") else "_x64")),
+            arch=(
+                "_x86"
+                if self.host == "windows"
+                else ("" if self.host in ("linux_arm64", "all_os", "windows_arm64") else "_x64")
+            ),
             target=self.target,
         )