[io] Fix for NumPy 1.24.0
@@ -53,7 +53,7 @@ def write_single_field(field: SampledField, file: str):
np.savez_compressed(file,
dim_names=dim_names,
dim_types=field.values.shape.types,
- dim_item_names=field.values.shape.item_names,
+ dim_item_names=np.asarray(field.values.shape.item_names, dtype=object),
field_type=type(field).__name__,
lower=lower,
upper=upper,
