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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(self, new: Statement) -> None: """Append a HistoryItem to end of the History list :param new: command line to convert to HistoryItem and add to the end of the History list """

        new = HistoryItem(new)
        list.append(self, new)
        new.idx = len(self)