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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def index(self, node: AbstractNode) -> int: """Return index of the node. If the node is not a child of this node, raise ``ValueError``. """

        if node in self.childNodes:
            return self.childNodes.index(node)
        elif isinstance(node, Text):
            for i, n in enumerate(self.childNodes):
                # should consider multiple match?
                if isinstance(n, Text) and n.data == node:
                    return i
        raise ValueError('node is not in this node')