rewrite the below Code into short, clean and precise(professional and structured) by follwing  below three points:
* try to more accurate and use common function
* try to understand everything so after you  got the logic you can do following.
* try to keep the code redundancy to a minimum, make use of viewset level settings + common functions,
* Make it as modular as possible.

Code:

def list(self, request, *args, **kwargs):
        cursor = self.request.query_params.get('cursor', None)
        paginator = self.get_paginator(cursor)
    
        location = filter_and_integerise(self.request.query_params.getlist('location_id', None))
        microlocation = filter_and_integerise(self.request.query_params.get('microlocation_id', None))
        
        current_version_code = request.user.app_version_code or 16
        
        post_id = self.request.query_params.get('post_id', None)
        # for easier testing
        es_feed_flag = self.request.query_params.get('es', False)
        content_formats = self.request.query_params.get('content_formats', '')
        # Location handling for recommendation
        if not location and post_id:
            location = [request.user.location_id]
    
        location_title, states, location_set = get_states(location)
    
        if states:
            es_feed_flag = True
    
        if settings.DJANGO_SERVER_ENVIRONMENT != "production":
            es_feed_flag = False
    
        user_day = filter_and_integerise(request.META.get('HTTP_DAY_COUNT', None))
    
        lokalints = LokalInts()
        if lokalints.CATEGORY_HOME_FEED is None:
            home_feed_categories = Category.objects.filter(is_active=True, is_home_feed=True).values_list("id", flat=True)
            lokalints.CATEGORY_HOME_FEED = list(home_feed_categories)

        # Content A/B test experiment
        user_cohort = ContentABTestManager.get_user_cohort(request.user.id, location_set)
    
        post_type = self.request.query_params.get('post_type', None)
        source = self.request.query_params.get('source', None)
    
        user_id = filter_and_integerise(self.request.query_params.get('user_id', None))
        category = filter_and_integerise(self.request.query_params.get('category_id', None))
    
        if post_id:
            recommendation_type = self.request.query_params.get('recommendation_type', 0)
            feed_type = self.request.query_params.get('feed_type', ArticlePageFeedType.SCROLL)
            if str(category) == str(settings.CATEGORY_ID_REAL_ESTATE):
                # Send empty recommendation for app version < 293
                # For version >=293, send chronologically sorted list of posts from same location.
                return self.get_real_estate_recommendations(paginator, post_id, post_type, request, user_day,
                                                            {'location_title': location_title, 'source': source,
                                                             'states': states,
                                                             'recommendation_type': recommendation_type,
                                                             'location_set': location_set,
                                                             'feed_type': feed_type,
                                                             'user_id': user_id or request.user.pk},
                                                            user_cohort)
            tags = self.request.query_params.getlist('tag_id', None)
            tags = filter_and_integerise(tags)
    
            return self.get_recommendations(paginator, post_id, post_type, request, user_day,
                                            {'location_title': location_title, 'source': source, 'states': states,
                                             'recommendation_type': recommendation_type, 'location_set': location_set,
                                             'feed_type': feed_type, 'user_id': user_id or request.user.pk,
                                             'content_formats': content_formats, 'category': category, 'tags': tags},
                                            user_cohort)
    
        if user_id is not None:
            submission_category = filter_and_integerise(request.query_params.getlist("submission_category"))
            return self.get_user_posts(paginator, user_id, request,
                                       {'location_title': location_title, 'location_set': location_set,
                                        'submission_category': submission_category})
    
        subcategories = filter_and_integerise(self.request.query_params.getlist('subcategory_id', None))
        tags = filter_and_integerise(self.request.query_params.getlist('tag_id', None))
    
        if category and str(category) == str(settings.CATEGORY_ID_REAL_ESTATE):
            return self.get_real_estate_feed(location_set, paginator, request, tags)
    
        if tags:
            return self.get_tagged_posts(paginator, post_type, tags, request, cursor, {'states': states,
                                                                                       'location_title': location_title,
                                                                                       'location_set': location_set},
                                         user_cohort, category)
        if not hasattr(request, 'uuid'):
            request.uuid = str(uuid.uuid4())
        if not hasattr(request, 'to_send'):
            percentage_to_log = Setting.get("PERCENTAGE_TO_LOG", default=10000)
            switch_post_logging = Setting.get("SWITCH_POST_LOGGING", default=False)
            request.to_send = randint(1, percentage_to_log) <= 1 and switch_post_logging
        start_time = time.time()
        queryset = self.get_posts_queryset(current_version_code, post_type, exclude_real_estate=True)
        if es_feed_flag:
            es_query = self.get_es_posts_query(current_version_code, post_type)
        requested_locale = request.LANGUAGE_CODE

        recommendations_config = request.query_params.get('config', "{}")
        try:
            recommendations_config = json.loads(recommendations_config)
        except JSONDecodeError:
            recommendations_config = dict()
        trending_variant = int(recommendations_config.get('trending_page', 0))

        # category_nonzero = list(filter(check_invalid, category))
        category_nonzero = category if check_invalid(category) else None
        filter_on_location = FilterOnLocation.DISTRICT_AND_STATE
        category_details = dict()
        # Check if category is to be filtered on location
        if category is not None:
            if category in [LokalInts.CATEGORY_LOCAL, LokalInts.CATEGORY_JOBS, LokalInts.CATEGORY_VIDEO]:
                filter_on_location = FilterOnLocation.DISTRICT_AND_STATE
            else:  # category > 2:
                try:
                    category_details = self.get_category_details(category)
                    filter_on_location = category_details['location_based_filtering']
                    # TODO: need to remove
                    if trending_variant != 0 and category_details.get('english_name') == 'Trending':
                        cursor_obj = paginator.decode_cursor_only(cursor)
                        if cursor_obj.reverse:
                            trending_feed = []
                        else:
                            trending_feed = self.get_trending_feed(category, location, trending_variant, cursor,
                                                                   user_cohort)
                        response = paginator.get_paginated_response(trending_feed)
                        return response
                except Category.DoesNotExist:
                    pass
        # For the categories which will have polls only
        if cursor is not None and category_details.get('posts_type', None) == CategoryType.POLLS_ONLY:
            pollviewset = PollViewSet()
            polls_response = pollviewset.list(request, *args, **kwargs)
            return polls_response

        # ! CATEGORY BASED FILTERING !
        # Show the category that has been asked for # checking for empty list
        if category_nonzero:
            queryset = queryset.filter(categories__id=category_nonzero)
            if es_feed_flag:
                es_query = es_query.query(esq('bool', must=[esq('nested', path='categories', query=esq('bool', should=[
                    esq('match', categories__id=category_nonzero)]))]))
        elif category == 0:
            queryset = queryset.filter(type=PostType.VIDEO)
            if es_feed_flag:
                es_query = es_query.query(esq('bool', must=esq('match', type=PostType.VIDEO)))
            campaign = get_user_campaign()
            if campaign:
                category_id = campaign.upload_category_id
                queryset = queryset.exclude(categories__id=category_id)
                if es_feed_flag:
                    es_query = es_query.query(
                        esq('bool', must=[esq('nested', path='categories', query=esq('bool', must_not=[
                            esq('match', categories__id=category_id)]))]))

        # ! SUBCATEGORY BASED FILTERING !
        if subcategories:
            queryset = queryset.filter(ugc_categories__id__in=subcategories)

return queryset