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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 set(self, time, value, compact=False):
 """Set the value for the time series. If compact is True, only set the value if it's different from what it would be anyway. """

        if (len(self) == 0) or (not compact) or \
                (compact and self.get(time) != value):
            self._d[time] = value