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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 append_transformed_structures(self, tstructs_or_transmuter):
 """ Method is overloaded to accept either a list of transformed structures or transmuter, it which case it appends the second transmuter"s structures. Args: tstructs_or_transmuter: A list of transformed structures or a transmuter. """

        if isinstance(tstructs_or_transmuter, self.__class__):
            self.transformed_structures.extend(tstructs_or_transmuter
                                               .transformed_structures)
        else:
            for ts in tstructs_or_transmuter:
                assert isinstance(ts, TransformedStructure)
            self.transformed_structures.extend(tstructs_or_transmuter)