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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 media_player_new(self, uri=None):
 """Create a new MediaPlayer instance. @param uri: an optional URI to play in the player. """

        p = libvlc_media_player_new(self)
        if uri:
            p.set_media(self.media_new(uri))
        p._instance = self
        return p