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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 prepare_series(self, memory: set) -> None: """Call |IOSequence.activate_ram| of all sequences selected by the given output element of the actual XML file. Use the memory argument to pass in already prepared sequences; newly prepared sequences will be added. False True True False False """

        for sequence in self._iterate_sequences():
            if sequence not in memory:
                memory.add(sequence)
                sequence.activate_ram()