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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 _fmtos(self):
 """An iterator over formatoption objects Contains only the formatoption whose keys are in all plotters in this list"""

        plotters = self.plotters
        if len(plotters) == 0:
            return {}
        p0 = plotters[0]
        if len(plotters) == 1:
            return p0._fmtos
        return (getattr(p0, key) for key in set(p0).intersection(
            *map(set, plotters[1:])))