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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 unrate_url(obj):
 """ Generates a link to "un-rate" the given object - this can be used as a form target or for POSTing via Ajax. """

    return reverse('ratings_unrate_object', args=(
        ContentType.objects.get_for_model(obj).pk,
        obj.pk,
    ))