code: def append_transformed_structures(self, tstructs_or_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)
docs: 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.