def METHOD_NAME(
    rng: np.random.Generator,
    x1_batch_shape: Optional[ShapeType],
    input_shape: ShapeType,
) -> Optional[np.ndarray]:
    """Random data from a standard normal distribution."""
    if x1_batch_shape is None:
        return None
    return rng.normal(0, 1, size=x1_batch_shape + input_shape)