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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 save(filename, n_frames=1, axis=np.array([0.,0.,1.]), clf=True, **kwargs):
 """Save frames from the viewer out to a file. Parameters filename : str The filename in which to save the output image. If more than one frame, should have extension .gif. n_frames : int Number of frames to render. If more than one, the scene will animate. axis : (3,) float or None If present, the animation will rotate about the given axis in world coordinates. Otherwise, the animation will rotate in azimuth. clf : bool If true, the Visualizer is cleared after rendering the figure. kwargs : dict Other keyword arguments for the SceneViewer instance. """

        if n_frames >1 and os.path.splitext(filename)[1] != '.gif':
            raise ValueError('Expected .gif file for multiple-frame save.')
        v = SceneViewer(Visualizer3D._scene,
                        size=Visualizer3D._init_size,
                        animate=(n_frames > 1),
                        animate_axis=axis,
                        max_frames=n_frames,
                        **kwargs)
        data = [m.data for m in v.saved_frames]
        if len(data) > 1:
            imageio.mimwrite(filename, data, fps=v._animate_rate, palettesize=128, subrectangles=True)
        else:
            imageio.imwrite(filename, data[0])

        if clf:
            Visualizer3D.clf()