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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 timeseries(self):
 """Simulated time series"""

        if self._timeseries is None:
            self.compute()
        if isinstance(self.system, NetworkModel):
            return self.system._reshape_timeseries(self._timeseries)
        else:
            return self._timeseries