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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 rebuildtable(cls):
 """Regenerate the entire closuretree."""

        cls._closure_model.objects.all().delete()
        cls._closure_model.objects.bulk_create([cls._closure_model(
            parent_id=x['pk'],
            child_id=x['pk'],
            depth=0
        ) for x in cls.objects.values("pk")])
        for node in cls.objects.all():
            node._closure_createlink()