def load_hands():
    """
    加载hand扩展插件

    :return: 返回hand注册字典(单例)
    :rtype: HandDict
    """
    # 优先进行自带 hand 的注册加载
    import mohand.decorator  # noqa

    # 注册hand插件
    mgr = stevedore.ExtensionManager(
        namespace=env.plugin_namespace,
        invoke_on_load=True)

    def register_hand(ext):
        _hand = ext.obj.register()
        if hasattr(hand, _hand.__name__):
            raise HandDuplicationOfNameError(_hand.__name__)
        hand[_hand.__name__] = _hand

        _pkg, _ver = ext.obj.version()
        env.version[_pkg] = _ver

    try:
        mgr.map(register_hand)
    except stevedore.exception.NoMatches:
        pass
    return hand
加载hand扩展插件

    :return: 返回hand注册字典(单例)
    :rtype: HandDict