code: def test_exists_s3(self):
      access_key_id = os.getenv("AWS_ACCESS_KEY_ID")
      secret_access_key = os.getenv("AWS_SECRET_ACCESS_KEY")
      if access_key_id and secret_access_key:
          file_path = "s3://analytics-zoo-data/nyc_taxi.csv"
          assert exists(file_path)
          file_path = "s3://analytics-zoo-data/abc.csv"
          assert not exists(file_path)
  
imports: import os.path
  import shutil
  import tempfile
  from zoo.orca.data.file import open_image, open_text, load_numpy, exists, makedirs, write_text
label_desc: Use image node_id 13 for calling the TestFile obj's underlying member method code with example usage: obj.test_exists_s3() without return types