Create a BM25Retriever from a list of texts. Args: texts: A list of texts to vectorize. metadatas: A list of metadata dicts to associate with each text. ids: A list of ids to associate with each text. bm25_params: Parameters to pass to the BM25 vectorizer. preprocess_func: A function to preprocess each text before vectorization. **kwargs: Any other arguments to pass to the retriever.
