[pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci

Author: pre-commit-ci[bot]

xarray/backends/file_manager.py

@@ -8,7 +8,7 @@
 from contextlib import AbstractContextManager, contextmanager
 from typing import Any, Generic, Literal, TypeVar, cast
 
-from xarray.backends.locks import acquire, NETCDF4_PYTHON_LOCK
+from xarray.backends.locks import acquire
 from xarray.backends.lru_cache import LRUCache
 from xarray.core import utils
 from xarray.core.options import OPTIONS