Constructs a ModelReference.

    Args:
        model_id (str): the ID of the model.

    Returns:
        google.cloud.bigquery.model.ModelReference:
            A ModelReference for a model in this dataset.

def _get_model_reference(self, model_id):
    """Constructs a ModelReference.

    Args:
        model_id (str): the ID of the model.

    Returns:
        google.cloud.bigquery.model.ModelReference:
            A ModelReference for a model in this dataset.
    """
    return ModelReference.from_api_repr(
        {"projectId": self.project, "datasetId": self.dataset_id, "modelId": model_id}
    )