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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 add_plot(self, *args, extension='pdf', **kwargs):
 """Add the current Matplotlib plot to the figure. The plot that gets added is the one that would normally be shown when using ``plt.show()``. Args ---- args: Arguments passed to plt.savefig for displaying the plot. extension : str extension of image file indicating figure file type kwargs: Keyword arguments passed to plt.savefig for displaying the plot. In case these contain ``width`` or ``placement``, they will be used for the same purpose as in the add_image command. Namely the width and placement of the generated plot in the LaTeX document. """


        add_image_kwargs = {}

        for key in ('width', 'placement'):
            if key in kwargs:
                add_image_kwargs[key] = kwargs.pop(key)

        filename = self._save_plot(*args, extension=extension, **kwargs)

        self.add_image(filename, **add_image_kwargs)