@classmethod
def from_range(cls, low, high):
    """
        Construct an intspanlist from the low value to the high value,
        inclusive. I.e., closed range, not the more typical Python
        half-open range.

        :param int low: Low bound.
        :param int high: High bound.
        :returns: New intspanlist low-high.
        :rtype: intspanlist
        """
    return cls(range(low, high + 1))
