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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 play_NoteContainer(self, nc, channel=1, velocity=100):
 """Play the Notes in the NoteContainer nc."""

        self.notify_listeners(self.MSG_PLAY_NC, {'notes': nc,
            'channel': channel, 'velocity': velocity})
        if nc is None:
            return True
        for note in nc:
            if not self.play_Note(note, channel, velocity):
                return False
        return True