def METHOD_NAME(self, docs):  # type: ignore[no-untyped-def]
    """Updates reference documents.
    Args:
        docs (List): List of documents to update.
    """
    for doc in docs:
        if doc.metadata["doc_id"] not in self._ref_docs:
            self._ref_docs[doc.metadata["doc_id"]] = []
        self._ref_docs[doc.metadata["doc_id"]].append(doc.id)
    self._save_ref_docs()