diff --git a/src/datasets/formatting/formatting.py b/src/datasets/formatting/formatting.py
index aafce2f68b8..ab76da3972e 100644
--- a/src/datasets/formatting/formatting.py
+++ b/src/datasets/formatting/formatting.py
@@ -205,12 +205,16 @@ def _arrow_array_to_numpy(self, pa_array: pa.Array) -> np.ndarray:
             if isinstance(pa_array.type, _ArrayXDExtensionType):
                 # don't call to_pylist() to preserve dtype of the fixed-size array
                 zero_copy_only = _is_zero_copy_only(pa_array.type.storage_dtype, unnest=True)
-                array: List = [row for chunk in pa_array.chunks for row in chunk.to_numpy(zero_copy_only=zero_copy_only)]
+                array: List = [
+                    row for chunk in pa_array.chunks for row in chunk.to_numpy(zero_copy_only=zero_copy_only)
+                ]
             else:
                 zero_copy_only = _is_zero_copy_only(pa_array.type) and all(
                     not _is_array_with_nulls(chunk) for chunk in pa_array.chunks
                 )
-                array: List = [row for chunk in pa_array.chunks for row in chunk.to_numpy(zero_copy_only=zero_copy_only)]
+                array: List = [
+                    row for chunk in pa_array.chunks for row in chunk.to_numpy(zero_copy_only=zero_copy_only)
+                ]
         else:
             if isinstance(pa_array.type, _ArrayXDExtensionType):
                 # don't call to_pylist() to preserve dtype of the fixed-size array