write the client.pem path.
        ca_pem_path (str): If use tls two-way authentication, need to write
            the ca.pem path.
        server_pem_path (str): If use tls one-way authentication, need to
            write the server.pem path.
        server_name (str): If use tls, need to write the common name.
    Example:
        .. code-block:: python
        from langchain import Milvus
        from langchain.embeddings import OpenAIEmbeddings
        embedding = OpenAIEmbeddings()
        # Connect to a milvus instance on localhost
        milvus_store = Milvus(
            embedding_function = Embeddings,
            collection_name = "LangChainCollection",
            drop_old = True,
        )
    Raises:
        ValueError: If the pymilvus python package is not installed.
    """
[docs]    def __init__(
        self,
        embedding_function: Embeddings,
        collection_name: str = "LangChainCollection",
        connection_args: Optional[dict[str, Any]] = None,
        consistency_level: str = "Session",
        index_params: Optional[dict] = None,
        search_params: Optional[dict] = None,
        drop_old: Optional[bool] = False,
    ):
        """Initialize the Milvus vector store."""
        try:
            from pymilvus import Collection, utility
        except ImportError:
            raise ValueError(
                "Could not import pymilvus python package. "
                "Please install it with `pip install pymilvus`."
            )
        # Default search params when one is not provided.
        self.default_search_params = {