code: def connection(self, host, port):
      connections.add_connection(default={"host": host, "port": port})
      connections.connect(alias="default")
  
      if connections.has_connection("default") is False:
          raise Exception("no connections")
      self.host = host
      self.port = port
  
imports: import threading
  import pytest
  import os
  import time
  import json
  from time import sleep
  from pymilvus import connections
  from chaos.checker import CollectionCreateChecker, InsertChecker, FlushChecker, SearchChecker, QueryChecker, IndexCreateChecker, DeleteChecker, Op
  from common.cus_resource_opts import CustomResourceOperations
  from utils.util_log import test_log
  from utils.util_k8s import wait_pods_ready, get_pod_list
  from utils.util_common import findkeys
  from chaos import chaos_commons
  from chaos.chaos_commons import assert_statistic
  from common.common_type import CaseLabel
  from chaos import constants
  from delayed_assert import assert_expectations
label_desc: Use image node_id 1 for calling the TestChaos obj's underlying member method code with example usage: obj.connection(host, port) without return types