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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 handle_request(self, request, app, model, pk):
 """Render and return tab"""

        ModelClass = self.get_model_class()
        object = ModelClass.objects.get(id=pk)

        tab_code = request.GET.get('tab')
        model_alias = request.GET.get('model_alias')
        model_alias = model_alias if model_alias else '{}.{}'.format(app, model)

        # TODO permission check

        item = tabs.get_tab(model_alias, object, tab_code)

        return item.get_layout(object).render(request)