code: def append_multi(self, keys, format=None, persist_to=0, replicate_to=0):
          
          return _Base.append_multi(self, keys, format=format,
                                    persist_to=persist_to,
                                    replicate_to=replicate_to)
docs: Append to multiple keys. Multi variant of :meth:`append`.
  
          .. warning::
  
              If using the `Item` interface, use the :meth:`append_items`
              and :meth:`prepend_items` instead, as those will
              automatically update the :attr:`.Item.value`
              property upon successful completion.
  
          .. seealso:: :meth:`append`, :meth:`upsert_multi`, :meth:`upsert`