def addkid(self, node, before=False):
        if before:  self.children.insert(0, node)
        else:   self.children.append(node)
        return self
Format:
dataset/ETHPy150Open timtadh/zhang-shasha/zss/simple_tree.py/Node.addkid--crossover with--dataset/ETHPy150Open limodou/par/par/bootstrap_ext.py/bootstrap_alert