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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 sys_hist(self, name=None):
 """ Return the effective low and high histogram for a given systematic. If this sample does not contain the named systematic then return the nominal histogram for both low and high variations. """

        if name is None:
            low = self.hist.Clone(shallow=True)
            high = self.hist.Clone(shallow=True)
            return low, high
        osys = self.GetOverallSys(name)
        hsys = self.GetHistoSys(name)
        if osys is None:
            osys_high, osys_low = 1., 1.
        else:
            osys_high, osys_low = osys.high, osys.low
        if hsys is None:
            hsys_high = self.hist.Clone(shallow=True)
            hsys_low = self.hist.Clone(shallow=True)
        else:
            hsys_high = hsys.high.Clone(shallow=True)
            hsys_low = hsys.low.Clone(shallow=True)
        return hsys_low * osys_low, hsys_high * osys_high