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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 add_tracks(self, subtracks):
 """ Add one or more tracks to this view. subtracks : Track or iterable of Tracks A single Track instance or an iterable of them. """

        if isinstance(subtracks, Track):
            subtracks = [subtracks]
        for subtrack in subtracks:
            subtrack.subgroups['view'] = self.view
            self.add_child(subtrack)
            self.subtracks.append(subtrack)