code: def clean_db(self):
      collection_names = self.show_collections()
      for name in collection_names:
          self.drop(collection_name=name)
  
imports: import random
  import logging
  import time
  from multiprocessing import Process
  from pymilvus import Milvus, DataType
  import utils
  import config
  from milvus_benchmark.runners import utils
label_desc: Use image node_id 33 for calling the MilvusClient obj's underlying member method code with example usage: obj.clean_db() without return types