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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 validate_link(link_data):
 """ Check if the given model exists, otherwise raise a Validation error """

    from django.apps import apps

    try:
        Model = apps.get_model(*link_data['model'].split('.'))
        Model.objects.get(pk=link_data['pk'])
    except Model.DoesNotExist:
        raise ValidationError(_("Unable to link onto '{0}'.").format(Model.__name__))