class_docstr: Test case of getting all collections 
class_docstr_tok: ["Test","case","of","getting","all","collections"]
code: def test_get_collections_by_prefix(
      self,
  ):
      self._connect()
      all_collections = self.utility_wrap.list_collections()[0]
      all_collections = [
          c_name for c_name in all_collections if "Checker" in c_name
      ]
      selected_collections_map = {}
      for c_name in all_collections:
          if (
              Collection(name=c_name).num_entities
              < constants.ENTITIES_FOR_SEARCH
          ):
              continue
          prefix = c_name.split("_")[0]
          if prefix not in selected_collections_map:
              selected_collections_map[prefix] = [c_name]
          else:
              if len(selected_collections_map[prefix]) <= 5:
                  selected_collections_map[prefix].append(c_name)
  
      selected_collections = []
      for value in selected_collections_map.values():
          selected_collections.extend(value)
      log.info(f"find {len(selected_collections)} collections:")
      log.info(selected_collections)
      data = {
          "all": selected_collections,
      }
      with open(
          "/tmp/ci_logs/chaos_test_all_collections.json", "w"
      ) as f:
          f.write(json.dumps(data))
      log.info(
          f"write {len(selected_collections)} collections to /tmp/ci_logs/chaos_test_all_collections.json"
      )
      collections_in_json = get_chaos_test_collections()
      assert len(selected_collections) == len(collections_in_json)
  
file_path: milvus/tests/python_client/chaos/testcases/test_get_collections.py
imports: import time
  import json
  from collections import defaultdict
  import pytest
  from pymilvus import Collection
  from base.client_base import TestcaseBase
  from deploy.common import get_chaos_test_collections
  from chaos import constants
  from common.common_type import CaseLabel
  from utils.util_log import test_log
label_desc: Use image node_id 1 for calling the TestGetCollections obj's underlying member method code with example usage: obj.test_get_collections_by_prefix() without return types