Convert a Nu Support Vector Regression (NuSVR) model to the protobuf spec.
    Parameters
    ----------
    model: NuSVR
        A trained NuSVR encoder model.

    feature_names: [str]
        Name of the input columns.

    target: str
        Name of the output column.

    Returns
    -------
    model_spec: An object of type Model_pb.
        Protobuf representation of the model

def convert(model, feature_names, target):
    """Convert a Nu Support Vector Regression (NuSVR) model to the protobuf spec.
    Parameters
    ----------
    model: NuSVR
        A trained NuSVR encoder model.

    feature_names: [str]
        Name of the input columns.

    target: str
        Name of the output column.

    Returns
    -------
    model_spec: An object of type Model_pb.
        Protobuf representation of the model
    """
    if not(_HAS_SKLEARN):
        raise RuntimeError('scikit-learn not found. scikit-learn conversion API is disabled.')

    _sklearn_util.check_expected_type(model, _NuSVR)
    return _SVR.convert(model, feature_names, target)