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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 nextElementSibling(self) -> Optional[AbstractNode]: """Next Element Node. If this node has no next element node, return None. """

        if self.parentNode is None:
            return None
        siblings = self.parentNode.childNodes
        for i in range(siblings.index(self) + 1, len(siblings)):
            n = siblings[i]
            if n.nodeType == Node.ELEMENT_NODE:
                return n
        return None