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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 get_empty_tracks(self):
 """ Return the indices of tracks with empty pianorolls. Returns ------- empty_track_indices : list The indices of tracks with empty pianorolls. """

        empty_track_indices = [idx for idx, track in enumerate(self.tracks)
                               if not np.any(track.pianoroll)]
        return empty_track_indices