code: def connection(self, host, port, milvus_ns):
      connections.add_connection(default={"host": host, "port": port})
      connections.connect(alias="default")
  
      if connections.has_connection("default") is False:
          raise Exception("no connections")
  
file_path: milvus/tests/python_client/bulk_insert/test_bulk_insert_perf_with_cohere_dataset.py
imports: import pytest
  import threading
  from time import sleep
  from pymilvus import connections, DataType, FieldSchema, CollectionSchema
  from chaos.checker import BulkInsertChecker, Op
  from utils.util_log import test_log
  from chaos import chaos_commons
  from common.common_type import CaseLabel
  from common import common_func
  from chaos import constants
  from delayed_assert import expect, assert_expectations
label_desc: Use image node_id 2 for calling the TestBUlkInsertPerf obj's underlying member method code with example usage: obj.connection(host, port, milvus_ns) without return types