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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 xpathCmpNodes(self, node2):
 """Compare two nodes w.r.t document order """

        if node2 is None: node2__o = None
        else: node2__o = node2._o
        ret = libxml2mod.xmlXPathCmpNodes(self._o, node2__o)
        return ret