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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 plot(self):
 """Show the running MOC on an all-sky map. This command requires that the Healpy and matplotlib libraries be available. It plots the running MOC, which should be normalized to a lower order first if it would generate an excessively large pixel array. :: pymoctool a.moc --normalize 8 --plot It also accepts additional arguments which can be used to control the plot. The 'order' option can be used instead of normalizing the MOC before plotting. The 'antialias' option specifies an additional number of MOC orders which should be used to smooth the edges as plotted -- 1 or 2 is normally sufficient. The 'file' option can be given to specify a file to which the plot should be saved. :: """


        if self.moc is None:
            raise CommandError('No MOC information present for plotting')

        from .plot import plot_moc

        order = self.moc.order
        antialias = 0
        filename = None

        while self.params:
            if self.params[-1] == 'order':
                self.params.pop()
                order = int(self.params.pop())
            elif self.params[-1] == 'antialias':
                self.params.pop()
                antialias = int(self.params.pop())
            elif self.params[-1] == 'file':
                self.params.pop()
                filename = self.params.pop()
            else:
                break

        plot_moc(self.moc, order=order, antialias=antialias,
                 filename=filename, projection='moll')