code: def object_exists(self, key):
      return key in self.obj_dict.keys()
  
imports: import time
  from io import BytesIO
  import pytest
  from ....None import dataframe
  from ....tests.core import mock
  from ..None import oss
  from .._oss_lib import glob
  from .._oss_lib.common import OSSFileEntry
  from ..oss import build_oss_path
label_desc: Use image node_id 3 for calling the SideEffectBucket obj's underlying member method code with example usage: obj.object_exists(key) and returns: unknown