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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):
 """Finds the first closest next sibling of the node which is an element node. Note the handling of entities references is different than in the W3C DOM element traversal spec since we don't have back reference from entities content to entities references. """

        ret = libxml2mod.xmlNextElementSibling(self._o)
        if ret is None:return None
        __tmp = xmlNode(_obj=ret)
        return __tmp