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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, video_name, out, start, duration):
 """ Trims a clip to be duration starting at start @param video_name : name of the input video @param out : name of the output video @param start : starting position after the trim @param duration : duration of video after start """

        command = ['ffmpeg', '-ss', start, '-i', video_name, '-c:v', 'huffyuv',
                   '-y', '-preset', 'veryslow', '-t', duration, out]
        if self.verbose:
            print 'Trimming {0} into {1}'.format(video_name, out)
            print ' '.join(command)
        call(command)