pub fn flat_bm25_search(
batch: RecordBatch,
doc_col: &str,
inverted_list: &InvertedListReader,
query_tokens: &HashSet<String>,
query_token_ids: &HashMap<String, Option<u32>>,
tokenizer: &mut TextAnalyzer,
avgdl: f32,
num_docs: usize,
) -> Result<RecordBatch, DataFusionError>