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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 generate_or_fail(self):
 """ Attempts to generate a random acyclic graph, raising an InvariantError if unable to. """


        t1 = self.generate_random_table()
        t2 = self.generate_random_table()
        f1 = self.generate_func(t1)
        f2 = self.generate_func(t2)
        edges = [(f1(word), f2(word)) for word in self.words]

        # Try to generate that graph, mack!
        # Note that failure to generate the graph here should be caught
        # by the caller.
        graph = forest.ForestGraph(edges=edges)

        # Associate each edge with its corresponding word.
        associations = {}
        for num in range(len(self.words)):
            edge = edges[num]
            word = self.words[num]
            associations[graph.canonical_order(edge)] = (num, word)

        # Assign all of these to the object.
        for name in ('t1', 't2', 'f1', 'f2', 'graph', 'associations'):
            self.__dict__[name] = locals()[name]