def DEFAULT_CALLBACKS():
    """
    Return the default callbacks,
    which will be used in :class:`TrainConfig` and :meth:`Trainer.train_with_defaults`.
    They are:

    1. MovingAverageSummary()
    2. ProgressBar()
    3. MergeAllSummaries()
    4. RunUpdateOps()
    """
    return [
        MovingAverageSummary(),
        ProgressBar(),
        MergeAllSummaries(),
        RunUpdateOps()]

    Return the default callbacks,
    which will be used in :class:`TrainConfig` and :meth:`Trainer.train_with_defaults`.
    They are:

    1. MovingAverageSummary()
    2. ProgressBar()
    3. MergeAllSummaries()
    4. RunUpdateOps()
    
tensorpack/train/config.py