diff --git a/nwb_linkml/tests/fixtures/nwb.py b/nwb_linkml/tests/fixtures/nwb.py
index 6c2390f..c878c74 100644
--- a/nwb_linkml/tests/fixtures/nwb.py
+++ b/nwb_linkml/tests/fixtures/nwb.py
@@ -461,7 +461,7 @@ def nwb_file(tmp_output_dir, nwb_file_base, request: pytest.FixtureRequest) -> P
     since there's not really a reason to
     """
     nwb_path = tmp_output_dir / "test_nwb.nwb"
-    if nwb_path.exists() and not request.config.getoption('--clean'):
+    if nwb_path.exists() and not request.config.getoption("--clean"):
         return nwb_path
 
     nwbfile = nwb_file_base
diff --git a/nwb_linkml/tests/fixtures/paths.py b/nwb_linkml/tests/fixtures/paths.py
index 5a8958b..d81304a 100644
--- a/nwb_linkml/tests/fixtures/paths.py
+++ b/nwb_linkml/tests/fixtures/paths.py
@@ -8,7 +8,7 @@ import pytest
 def tmp_output_dir(request: pytest.FixtureRequest) -> Path:
     path = Path(__file__).parent.resolve() / "__tmp__"
     if path.exists():
-        if request.config.getoption('--clean'):
+        if request.config.getoption("--clean"):
             shutil.rmtree(path)
         else:
             for subdir in path.iterdir():