A feature of filters is missing from assistant

[JavanTang]

What I'm looking at in vectordb, it actually has some databases that support this filters feature:phi/vectordb/pgvector/pgvector2.py

But in fact, there is no relevant implementation in the assistant, such as the following code:

    def get_references_from_knowledge_base(self, query: str, num_documents: Optional[int] = None) -> Optional[str]:
        """Return a list of references from the knowledge base"""

        if self.references_function is not None:
            reference_kwargs = {"assistant": self, "query": query, "num_documents": num_documents}
            return remove_indent(self.references_function(**reference_kwargs))

        if self.knowledge_base is None:
            return None

        relevant_docs: List[Document] = self.knowledge_base.search(query=query, num_documents=num_documents)
        if len(relevant_docs) == 0:
            return None

        if self.references_format == "yaml":
            import yaml

            return yaml.dump([doc.to_dict() for doc in relevant_docs])

        return json.dumps([doc.to_dict() for doc in relevant_docs], indent=2)

I think a feature for this could be added