class_docstr: Interface class for storage systems.
  
  A key -> multiple distinct values mapping.
  
  Keys and values are binary data.
docstr: Return all values matching this key.
docstr_tok: ["Return","all","values","matching","this","key","."]
code: def fetch(self, key):
      """Return all values matching this key."""
      raise NotImplementedError("%s.fetch" % (type(self).__name__))
  
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 4 for calling the ExampleDatabase obj's underlying member method code with example usage: obj.fetch(key) without return types