class_docstr: Interface of updater objects for trainers.
  
  :class:`~chainer.training.Updater` implements a training iteration
  as :meth:`update`. Typically, the updating iteration proceeds as follows.
  
  - Fetch a minibatch from :mod:`~chainer.dataset`
    via :class:`~chainer.dataset.Iterator`.
  - Run forward and backward process of :class:`~chainer.Chain`.
  - Update parameters according to their :class:`~chainer.UpdateRule`.
  
  The first line is processed by
  :meth:`Iterator.__next__ <chainer.dataset.Iterator.__next__>`.
  The second and third are processed by
  :meth:`Optimizer.update <chainer.Optimizer.update>`.
  Users can also implement their original updating iteration by overriding
  :meth:`Updater.update <chainer.training.Updater.update>`.
docstr: Serializes the current state of the updater object.
docstr_tok: ["Serializes","the","current","state","of","the","updater","object","."]
code: def serialize(self, serializer):
      """Serializes the current state of the updater object."""
      raise NotImplementedError
  
file_path: chainer/chainer/training/_updater.py
label_desc: Use image node_id 6 for calling the Updater obj's underlying member method code with example usage: obj.serialize(serializer) without return types