code: def __getitem__(self, key: Any) -> Any:
      try:
          self._check_if_crashed()
          value = super().__getitem__(key)
          return value
      except KeyError as e:
          if self._ddtype:
              return self._ddtype()
          raise e
  
imports: from typing import Any
  from typing import Type
  from syft.serde.serializable import serializable
  from syft.store.document_store import DocumentStore
  from syft.store.document_store import PartitionSettings
  from syft.store.document_store import StoreConfig
  from syft.store.kv_document_store import KeyValueBackingStore
  from syft.types.syft_object import SyftObject
  from syft.types.uid import UID
label_desc: Use image node_id 4 for calling the MockKeyValueBackingStore obj's underlying member method code with example usage: obj.__getitem__(key) and returns: value, self