How to use the icrawler.utils.proxy_pool.Proxy function in icrawler

def load(self, filename):
        """Load proxies from file"""
        with open(filename, 'r') as fin:
            proxies = json.load(fin)
        for protocol in proxies:
            for proxy in proxies[protocol]:
                self.proxies[protocol][proxy['addr']] = Proxy(
                    proxy['addr'], proxy['protocol'], proxy['weight'],
                    proxy['last_checked'])
                self.addr_list[protocol].append(proxy['addr'])

candidate_proxy = proxy_scanner.proxy_queue.get(
                    timeout=queue_timeout)
            except queue.Empty:
                if proxy_scanner.is_scanning():
                    continue
                else:
                    break
            addr = candidate_proxy['addr']
            protocol = candidate_proxy['protocol']
            ret = self.is_valid(addr, protocol, val_timeout)
            if self.proxy_num() >= expected_num:
                self.logger.info('Enough valid proxies, thread {} exit.'
                                 .format(threading.current_thread().name))
                break
            if ret['valid']:
                self.add_proxy(Proxy(addr, protocol))
                self.logger.info('{} ok, {:.2f}s'.format(addr, ret[
                    'response_time']))
            else:
                self.logger.info('{} invalid, {}'.format(addr, ret['msg']))