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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 _compile_seriesflow(self):
 """Post power flow computation of series device flow"""

        string = '"""\n'
        for device, pflow, series in zip(self.devices, self.pflow,
                                         self.series):
            if pflow and series:
                string += 'system.' + device + '.seriesflow(system.dae)\n'
        string += '\n'
        string += '"""'
        self.seriesflow = compile(eval(string), '', 'exec')