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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 lookup_track(self, track):
 """ Looks up Django Track object for provided raw importing track object. """

        tracks = Track.objects.filter(title__iexact=track.title)
        for track_obj in tracks:
            for contributor in track_obj.get_primary_contributors(permitted=False):
                if contributor.title == track.artist:
                    return track_obj
        return None