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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 trim(self, n='all', x=True, y=True):
 """ This will set xmin and xmax based on the current zoom-level of the figures. n='all' Which figure to use for setting xmin and xmax. 'all' means all figures. You may also specify a list. x=True Trim the x-range y=True Trim the y-range """

        if len(self._set_xdata)==0 or len(self._set_ydata)==0:
            self._error("No data. Please use set_data() and plot() prior to trimming.")
            return
        
        if _s.fun.is_a_number(n): n = [n]
        elif isinstance(n,str):   n = list(range(len(self._set_xdata)))

        # loop over the specified plots
        for i in n:
            try:
                if x:
                    xmin, xmax = _p.figure(self['first_figure']+i).axes[1].get_xlim()
                    self['xmin'][i] = xmin
                    self['xmax'][i] = xmax

                if y:
                    ymin, ymax = _p.figure(self['first_figure']+i).axes[1].get_ylim()
                    self['ymin'][i] = ymin
                    self['ymax'][i] = ymax

            except:
                self._error("Data "+str(i)+" is not currently plotted.")

        # now show the update.
        self.clear_results()
        if self['autoplot']: self.plot()

        return self