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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 set_music(self, plylst, force=False):
        '''
        Use to set the playlist to @plylst. If @force is False, the playlist 
        will not be set if it is @plylst already.
        '''
        plylst = plylst.lower()
        if plylst != self.cur_playlist or force:
            self.cur_playlist = plylst
            self.play_song(self.get_playlist().begin())