def get_user_agent(module: Optional[str] = None) -> Tuple[str, str]:
    r"""
    Returns a custom user agent header.

    Args:
        module (Optional[str]):
            Optional. The module for a custom user agent header.

    Returns:
        Tuple[str, str]

    """
    try:
        llamaindex_version = metadata.version(
            "llama-index-vector-stores-vertexaivectorsearch"
        )
    except metadata.PackageNotFoundError:
        llamaindex_version = "0.0.0"
    client_library_version = (
        f"{llamaindex_version}-{module}" if module else llamaindex_version
    )
    return (
        client_library_version,
        f"llama-index-vector-stores-vertexaivectorsearch/{client_library_version}",
    )

    Returns a custom user agent header.

    Args:
        module (Optional[str]):
            Optional. The module for a custom user agent header.

    Returns:
        Tuple[str, str]

    
llama-index-integrations/vector_stores/llama-index-vector-stores-vertexaivectorsearch/llama_index/vector_stores/vertexaivectorsearch/utils.py