diff --git a/platform_storage_api/api.py b/platform_storage_api/api.py
index b336590..0918f28 100644
--- a/platform_storage_api/api.py
+++ b/platform_storage_api/api.py
@@ -771,12 +771,12 @@ async def handle_error_if_streamed(
     error_class: type[web.HTTPError] = web.HTTPBadRequest,
 ) -> None:
     if response.prepared:
-        error_dict = dict(
-            error=str_error,
-            errno=errorcode[errno]
-            if errno is not None and errno in errorcode
-            else errno,
-        )
+        error_dict = {
+            "error": str_error,
+            "errno": (
+                errorcode[errno] if errno is not None and errno in errorcode else errno
+            ),
+        }
         await response.write(json.dumps(error_dict).encode())
     else:
         raise _http_exception(error_class, str_error, errno=errno)
@@ -862,7 +862,7 @@ def make_tracing_trace_configs(config: Config) -> list[aiohttp.TraceConfig]:
 async def create_app(config: Config) -> web.Application:
     app = web.Application(
         middlewares=[handle_exceptions],
-        handler_args=dict(keepalive_timeout=config.server.keep_alive_timeout_s),
+        handler_args={"keepalive_timeout": config.server.keep_alive_timeout_s},
     )
     app[CONFIG_KEY] = config
 
diff --git a/platform_storage_api/fs/local.py b/platform_storage_api/fs/local.py
index 1950302..7edbcfa 100644
--- a/platform_storage_api/fs/local.py
+++ b/platform_storage_api/fs/local.py
@@ -363,22 +363,21 @@ async def _iterate_in_chunks(
             yield chunk
 
     def _scandir_iter(self, path: PurePath) -> Iterator[FileStatus]:
-        with self._resolve_dir_fd(path) as dirfd:
-            with os.scandir(dirfd) as scandir_it:
-                for entry in scandir_it:
-                    if entry.is_symlink():
-                        target = os.readlink(entry.name, dir_fd=dirfd)
-                        yield self._create_linkstatus(
-                            PurePath(entry.name),
-                            entry.stat(follow_symlinks=False),
-                            target=target,
-                        )
-                    else:
-                        yield self._create_filestatus(
-                            PurePath(entry.name),
-                            entry.stat(follow_symlinks=False),
-                            entry.is_dir(follow_symlinks=False),
-                        )
+        with self._resolve_dir_fd(path) as dirfd, os.scandir(dirfd) as scandir_it:
+            for entry in scandir_it:
+                if entry.is_symlink():
+                    target = os.readlink(entry.name, dir_fd=dirfd)
+                    yield self._create_linkstatus(
+                        PurePath(entry.name),
+                        entry.stat(follow_symlinks=False),
+                        target=target,
+                    )
+                else:
+                    yield self._create_filestatus(
+                        PurePath(entry.name),
+                        entry.stat(follow_symlinks=False),
+                        entry.is_dir(follow_symlinks=False),
+                    )
 
     async def _iterstatus_iter(
         self, dir_iter: Iterator[FileStatus]
@@ -566,11 +565,11 @@ async def remove(self, path: PurePath, *, recursive: bool = False) -> None:
         await self._loop.run_in_executor(self._executor, self._remove, path, recursive)
 
     def _rename(self, old: PurePath, new: PurePath) -> None:
-        with self._resolve_dir_fd(old.parent) as src_dir_fd:
-            with self._resolve_dir_fd(new.parent) as dst_dir_fd:
-                os.rename(
-                    old.name, new.name, src_dir_fd=src_dir_fd, dst_dir_fd=dst_dir_fd
-                )
+        with (
+            self._resolve_dir_fd(old.parent) as src_dir_fd,
+            self._resolve_dir_fd(new.parent) as dst_dir_fd,
+        ):
+            os.rename(old.name, new.name, src_dir_fd=src_dir_fd, dst_dir_fd=dst_dir_fd)
 
     async def rename(self, old: PurePath, new: PurePath) -> None:
         await self._loop.run_in_executor(self._executor, self._rename, old, new)
diff --git a/platform_storage_api/storage.py b/platform_storage_api/storage.py
index 06032d5..883ba3c 100644
--- a/platform_storage_api/storage.py
+++ b/platform_storage_api/storage.py
@@ -189,7 +189,7 @@ async def rename(
 
     @trace
     async def disk_usage(
-        self, path: Optional[Union[PurePath, str]] = None
+        self, path: Union[PurePath, str, None] = None
     ) -> DiskUsageInfo:
         real_path = await self._path_resolver.resolve_path(PurePath(path or "/"))
         return await self._fs.disk_usage(real_path)
diff --git a/tests/integration/test_api_sharing_resources.py b/tests/integration/test_api_sharing_resources.py
index fbff3a7..8782950 100644
--- a/tests/integration/test_api_sharing_resources.py
+++ b/tests/integration/test_api_sharing_resources.py
@@ -9,9 +9,9 @@
 import yarl
 
 from platform_storage_api.fs.local import FileStatusType
+from tests.integration.conftest import ApiConfig, status_iter_response_to_list
 
 from .auth import _User, _UserFactory
-from tests.integration.conftest import ApiConfig, status_iter_response_to_list
 
 
 class TestStorageListAndResourceSharing:
diff --git a/tests/integration/test_api_websocket.py b/tests/integration/test_api_websocket.py
index b02fc20..75560f1 100644
--- a/tests/integration/test_api_websocket.py
+++ b/tests/integration/test_api_websocket.py
@@ -12,14 +12,14 @@
 
 from platform_storage_api.api import WSStorageOperation
 from platform_storage_api.fs.local import FileStatusType
-
-from .auth import _User, _UserFactory
 from tests.integration.conftest import (
     ApiConfig,
     get_filestatus_dict,
     get_liststatus_dict,
 )
 
+from .auth import _User, _UserFactory
+
 
 def ws_request(
     op: WSStorageOperation, id: int, path: Optional[str] = None, **kwargs: Any