def METHOD_NAME():
    import nnabla
    import nnabla.utils.callback as callback
    version_string = 'Version:{}, Build:{}'.format(nnabla.__version__,
                                                   nnabla.__build_number__)
    callback_version_string = callback.get_callback_version()
    if callback_version_string is not None:
        version_string += ', Callback:{}'.format(callback_version_string)
    return version_string