How to use the pyreferrer.referrer.Referrer.parse_query_string function in pyreferrer

'tld': domain_info.suffix or user_agent_info['tld'],
            'path': url.path,
            'query': ''
        }

        if Referrer.is_valid_url(url, domain_info):
            # First check for an exact match of the url. Then check for a match with different combinations of domain, subdomain and tld
            known_url = rules.get(url.netloc + url.path) \
                or rules.get(domain_info.registered_domain + url.path) \
                or rules.get(url.netloc) \
                or rules.get(domain_info.registered_domain)

            if known_url:
                referrer['label'] = known_url['label']
                referrer['type'] = known_url['type']
                referrer['query'] = Referrer.parse_query_string(url, known_url.get('parameters'))
        elif user_agent_info['registered_domain']:
            known_url = rules.get(user_agent_info['registered_domain'])

            if known_url:
                referrer['label'] = known_url['label']
                referrer['type'] = known_url['type']
                referrer['query'] = Referrer.parse_query_string(url, known_url.get('parameters'))
        else:
            referrer['type'] = Referrer.Types.INVALID if raw_url else Referrer.Types.DIRECT
        return referrer

'tld': domain_info.suffix or user_agent_info['tld'],
            'path': url.path,
            'query': ''
        }

        if Referrer.is_valid_url(url, domain_info):
            # First check for an exact match of the url. Then check for a match with different combinations of domain, subdomain and tld
            known_url = rules.get(url.netloc + url.path)\
                                    or rules.get(domain_info.registered_domain + url.path)\
                                    or rules.get(url.netloc)\
                                    or rules.get(domain_info.registered_domain)
            
            if known_url:
                referrer['label'] = known_url['label']
                referrer['type'] = known_url['type']
                referrer['query'] = Referrer.parse_query_string(url, known_url.get('parameters'))
        elif user_agent_info['registered_domain']:
            known_url = rules.get(user_agent_info['registered_domain'])

            if known_url:
                referrer['label'] = known_url['label']
                referrer['type'] = known_url['type']
                referrer['query'] = Referrer.parse_query_string(url, known_url.get('parameters'))
        else:
            referrer['type'] = Referrer.Types.INVALID if raw_url else Referrer.Types.DIRECT

        referrer['google_search_type'] = Referrer.google_search_type(referrer['type'], referrer['label'], referrer['path'])

        return referrer