def _bbox(nodes):
    """Get the bounding box for set of points.

    .. note::

       There is also a Fortran implementation of this function, which
       will be used if it can be built.

    Args:
       nodes (numpy.ndarray): A set of points.

    Returns:
        Tuple[float, float, float, float]: The left, right,
        bottom and top bounds for the box.
    """
    left, bottom = np.min(nodes, axis=1)
    right, top = np.max(nodes, axis=1)
    return left, right, bottom, top