def _interval_to_bound_points(array: Sequence[pd.Interval]) -> np.ndarray:
    """
    Helper function which returns an array
    with the Intervals' boundaries.
    """

    array_boundaries = np.array([x.left for x in array])
    array_boundaries = np.concatenate((array_boundaries, np.array([array[-1].right])))

    return array_boundaries

    Helper function which returns an array
    with the Intervals' boundaries.
    
xarray/plot/utils.py