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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 output(self):
 """Simulated model output"""

        if self._timeseries is None:
            self.compute()
        output = self._timeseries[:, self.system.output_vars]
        if isinstance(self.system, NetworkModel):
            return self.system._reshape_output(output)
        else:
            return output