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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 last_timestamp(self, sid, epoch=False):
 """ Get the theoretical last timestamp for a sensor Parameters sid : str SensorID epoch : bool default False If True return as epoch If False return as pd.Timestamp Returns ------- pd.Timestamp | int """

        timestamp, value = self.last_datapoint(sid, epoch)
        return timestamp