language:af language:en language:nso language:sot language:ssw language:tsn language:tso language:ven language:xho language:zul language:nbl license:apache-2.0 size_categories:1M<n<10M format:parquet format:optimized-parquet modality:text library:datasets library:dask library:polars library:mlcroissant arxiv:2603.20732 region:us pretraining south-african-languages multilingual mzansitext