def _nearest_overlapping_point(src, point):
    """Find the interval with the closest start point to a given point.

    :param src: IntervalTree instance.
    :param point: query point.

    :returns: Interval instance of interval with closest start.

    """
    items = src.at(point)
    if len(items) == 0:
        return None
    items = sorted(items, key=lambda x: x.end - x.begin, reverse=True)
    items.sort(key=lambda x: abs(x.begin - point))
    return items[0]
