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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 open_movie(self, filename, framerate=24):
 """ Establishes a connection to the ffmpeg writer Parameters filename : str Filename of the movie to open. Filename should end in mp4, but other filetypes may be supported. See "imagio.get_writer" framerate : int, optional Frames per second. """

        if isinstance(vtki.FIGURE_PATH, str) and not os.path.isabs(filename):
            filename = os.path.join(vtki.FIGURE_PATH, filename)
        self.mwriter = imageio.get_writer(filename, fps=framerate)