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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 traverse(self, index=0):
 """ This is used to produce a list of lists where each each item in that list is a diffrent combination of items from the lists within with every combination of such values. Args: index (int) : the index at witch to start the list. Note this is used only in the function as a processing Returns: list : is every combination. """

        if index < len(self.nodes):
            for entity in self.nodes[index]:
                for next_result in self.traverse(index=index+1):
                    if isinstance(entity, list):
                        yield entity + next_result
                    else:
                        yield [entity] + next_result
        else:
            yield []