code: def fetch(self, key):
      kp = self._key_path(key)
      if not os.path.exists(kp):
          return
      for path in os.listdir(kp):
          try:
              with open(os.path.join(kp, path), "rb") as i:
                  yield hbytes(i.read())
          except EnvironmentError:
              pass
  
imports: from __future__ import absolute_import, division, print_function
  import binascii
  import os
  import warnings
  from hashlib import sha384
  from hypothesis.configuration import mkdir_p, storage_directory
  from hypothesis.errors import HypothesisException, HypothesisWarning
  from hypothesis.internal.compat import hbytes
  from hypothesis.utils.conventions import not_set
label_desc: Use image node_id 6 for calling the DirectoryBasedExampleDatabase obj's underlying member method code with example usage: obj.fetch(key) without return types