def _extract(param_names: List[str],
             params: Dict[str, mx.nd.NDArray],
             ext_params: Dict[str, np.ndarray]) -> List[str]:
    """
    Extract specific parameters from a given base.

    :param param_names: Names of parameters to be extracted.
    :param params: Mapping from parameter names to the actual NDArrays parameters.
    :param ext_params: Extracted parameter dictionary.
    :return: Remaining names of parameters to be extracted.
    """
    remaining_param_names = list(param_names)
    for name in param_names:
        if name in params:
            logger.info("\tFound '%s': shape=%s", name, str(params[name].shape))
            ext_params[name] = params[name].asnumpy()
            remaining_param_names.remove(name)
    return remaining_param_names
Extract specific parameters from a given base.

    :param param_names: Names of parameters to be extracted.
    :param params: Mapping from parameter names to the actual NDArrays parameters.
    :param ext_params: Extracted parameter dictionary.
    :return: Remaining names of parameters to be extracted.