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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 autocomplete_view(self, request):
 """ Searches in the fields of the given related model and returns the result as a simple string to be used by the jQuery Autocomplete plugin """

        query = request.GET.get('q', None)
        app_label = request.GET.get('app_label', None)
        model_name = request.GET.get('model_name', None)
        search_fields = request.GET.get('search_fields', None)
        object_pk = request.GET.get('object_pk', None)

        try:
            to_string_function = self.related_string_functions[model_name]
        except KeyError:
            to_string_function = lambda x: str(x)

        if search_fields and app_label and model_name and (query or object_pk):

            def construct_search(field_name):
                # use different lookup methods depending on the notation
                if field_name.startswith('^'):
                    fmt, name = "{}__istartswith", field_name[1:]
                elif field_name.startswith('='):
                    fmt, name = "{}__iexact", field_name[1:]
                elif field_name.startswith('@'):
                    fmt, name = "{}__search", field_name[1:]
                else:
                    fmt, name = "{}__icontains", field_name
                return fmt.format(name)

            model = apps.get_model(app_label, model_name)
            queryset = model._default_manager.all()
            data = ''
            if query:
                for bit in query.split():
                    or_queries = [
                        models.Q(**{construct_search(smart_str(field_name)): smart_str(bit)})
                        for field_name
                        in search_fields.split(',')
                    ]
                    other_qs = QuerySet(model)
                    other_qs.query.select_related = queryset.query.select_related
                    other_qs = other_qs.filter(reduce(operator.or_, or_queries))
                    queryset = queryset & other_qs

                if self.autocomplete_limit:
                    queryset = queryset[:self.autocomplete_limit]

                data = ''.join([
                    '{}|{}\n'.format(to_string_function(f), f.pk)
                    for f
                    in queryset
                ])
            elif object_pk:
                try:
                    obj = queryset.get(pk=object_pk)
                except:
                    pass
                else:
                    data = to_string_function(obj)
            return HttpResponse(data)
        return HttpResponseNotFound()