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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 FPPplots(self, folder=None, format='png', tag=None, **kwargs):
 """ Make FPP diagnostic plots Makes likelihood "fuzz plot" for each model, a FPP summary figure, a plot of the :class:`TransitSignal`, and writes a ``results.txt`` file. :param folder: (optional) Destination folder for plots/``results.txt``. Default is ``self.folder``. :param format: (optional) :param tag: (optional) If this is provided (string), then filenames will have ``_[tag]`` appended to the filename, before the extension. :param **kwargs: Additional keyword arguments passed to :func:`PopulationSet.lhoodplots`. """

        if folder is None:
            folder = self.folder

        self.write_results(folder=folder)
        self.lhoodplots(folder=folder,figformat=format,tag=tag,**kwargs)
        self.FPPsummary(folder=folder,saveplot=True,figformat=format,tag=tag)
        self.plotsignal(folder=folder,saveplot=True,figformat=format)