<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def remove_tracks(self, track_indices):
 """ Remove tracks specified by `track_indices`. Parameters track_indices : list The indices of the tracks to be removed. """

        if isinstance(track_indices, int):
            track_indices = [track_indices]
        self.tracks = [track for idx, track in enumerate(self.tracks)
                       if idx not in track_indices]