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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 replaceChild(self, new_child: 'WdomElement', old_child: 'WdomElement' ) -> Node: """Replace child nodes."""

        if self.connected:
            self._replace_child_web(new_child, old_child)
        return self._replace_child(new_child, old_child)