"""Force system to keep model in RAM."""
    n_threads: Optional[int] = Field(None, alias="n_threads")
    """Number of threads to use. If None, the number 
    of threads is automatically determined."""
    n_batch: Optional[int] = Field(8, alias="n_batch")
    """Number of tokens to process in parallel.
    Should be a number between 1 and n_ctx."""
    n_gpu_layers: Optional[int] = Field(None, alias="n_gpu_layers")
    """Number of layers to be loaded into gpu memory. Default None."""
    verbose: bool = Field(True, alias="verbose")
    """Print verbose output to stderr."""
    class Config:
        """Configuration for this pydantic object."""
        extra = Extra.forbid
    @root_validator()
    def validate_environment(cls, values: Dict) -> Dict:
        """Validate that llama-cpp-python library is installed."""
        model_path = values["model_path"]
        model_param_names = [
            "n_ctx",
            "n_parts",
            "seed",
            "f16_kv",
            "logits_all",
            "vocab_only",
            "use_mlock",
            "n_threads",
            "n_batch",
            "verbose",
        ]
        model_params = {k: values[k] for k in model_param_names}
        # For backwards compatibility, only include if non-null.
        if values["n_gpu_layers"] is not None:
            model_params["n_gpu_layers"] = values["n_gpu_layers"]
        try:
            from llama_cpp import Llama
            values["client"] = Llama(model_path, embedding=True, **model_params)
        except ImportError:
            raise ModuleNotFoundError(