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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 inverse(self):
 """ Return the inverse of the graph. @rtype: graph @return: Complement graph for the graph. """

        inv = self.__class__()
        inv.add_nodes(self.nodes())
        inv.complete()
        for each in self.edges():
            if (inv.has_edge(each)):
                inv.del_edge(each)
        return inv