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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 get_object(self):
 """ Fetch a single document from the data store according to whatever unique identifier is available for that document in the SearchIndex. In cases where the view has multiple ``index_models``, add a ``model`` query parameter containing a single `app_label.model` name to the request in order to override which model to include in the SearchQuerySet. Example: /api/v1/search/42/?model=myapp.person """

        queryset = self.get_queryset()
        if "model" in self.request.query_params:
            try:
                app_label, model = map(six.text_type.lower, self.request.query_params["model"].split(".", 1))
                ctype = ContentType.objects.get(app_label=app_label, model=model)
                queryset = self.get_queryset(index_models=[ctype.model_class()])
            except (ValueError, ContentType.DoesNotExist):
                raise Http404("Could not find any models matching '%s'. Make sure to use a valid "
                              "'app_label.model' name for the 'model' query parameter." % self.request.query_params["model"])

        lookup_url_kwarg = self.lookup_url_kwarg or self.lookup_field
        if lookup_url_kwarg not in self.kwargs:
            raise AttributeError(
                "Expected view %s to be called with a URL keyword argument "
                "named '%s'. Fix your URL conf, or set the `.lookup_field` "
                "attribute on the view correctly." % (self.__class__.__name__, lookup_url_kwarg)
            )
        queryset = queryset.filter(self.query_object((self.document_uid_field, self.kwargs[lookup_url_kwarg])))
        count = queryset.count()
        if count == 1:
            return queryset[0]
        elif count > 1:
            raise Http404("Multiple results matches the given query. Expected a single result.")

        raise Http404("No result matches the given query.")