diff --git a/src/openai/lib/_validators.py b/src/openai/lib/_validators.py
index ae48aafa88..e36f0e95fb 100644
--- a/src/openai/lib/_validators.py
+++ b/src/openai/lib/_validators.py
@@ -309,7 +309,7 @@ def common_completion_prefix_validator(df: pd.DataFrame) -> Remediation:
         return Remediation(name="common_prefix")
 
     def remove_common_prefix(x: Any, prefix: Any, ws_prefix: Any) -> Any:
-        x["completion"] = x["completion"].str[len(prefix):]
+        x["completion"] = x["completion"].str[len(prefix) :]
         if ws_prefix:
             # keep the single whitespace as prefix
             x["completion"] = f" {x['completion']}"
@@ -623,9 +623,7 @@ def get_outfnames(fname: str, split: bool) -> list[str]:
     i = 0
     while True:
         index_suffix = f" ({i})" if i > 0 else ""
-        candidate_fnames = [
-            f"{os.path.splitext(fname)[0]}_prepared{suffix}{index_suffix}.jsonl" for suffix in suffixes
-        ]
+        candidate_fnames = [f"{os.path.splitext(fname)[0]}_prepared{suffix}{index_suffix}.jsonl" for suffix in suffixes]
         if not any(os.path.isfile(f) for f in candidate_fnames):
             return candidate_fnames
         i += 1