Simple tree structure (python)

class TreeNode(object):

    def __init__(self):
        self.subnodes = []
        self.parent   = None

    def addNode(self, node):
        self.subnodes.append(node)
        node.parent = self

    def insertNode(self, index, node):
        self.subnodes.insert(index, node)
        node.parent = self

    def removeNode(self, node):
        self.subnodes.remove(node)
        node.parent = None

    def removeNodeRecursively(self, node):
        try:
            self.subnodes.remove(node)
            node.parent = None
            return True
        except ValueError:
            for node in self.subnodes:
                if node.removeNodeRecursively(node):
                    return True
            return False

    def getNode(self, index):
        return self.subnodes[index]

    def setNodes(self, subnodes):
        for node in subnodes:
            node.parent = self
        self.subnodes = list(subnodes)