fix lint

Author: dmandache

tests/test_parse.py

@@ -573,7 +573,8 @@ def update(self, amount):
 
 def test_process_with_checkpoint_rejects_non_positive_frequency(tmp_path):
     df_paths = pd.DataFrame({"dicom_path": ["a.dcm"]})
-    read_func = lambda _: pd.Series({"PatientName": "x"})
+    def read_func(_):
+        return pd.Series({"PatientName": "x"})
 
     with pytest.raises(ValueError, match="positive integer"):
         parse.process_with_checkpoint(