def descendantset(self, starts, stops=None):
    '\n        set of all descendants of starts (incl), but stop walk at stops (excl)\n        '
    return self.inverse().ancestorset(starts, stops)
set of all descendants of starts (incl), but stop walk at stops (excl)
def descendantset(self, starts, stops=None):
    '\n        \n        '
    return self.inverse().ancestorset(starts, stops)