def _class_get_plugin(cls):
    """
    Class method that retrieves the plugin instance associated
    with the current model class.
    This method should not overlap the get plugin method on the
    instance, and you should used this one to retrieve the absolute
    related system instance, avoiding problems with inheritance.

    :rtype: Plugin
    :return: The plugin instance associated with the current
    model class.
    """

    return cls._system_instance.plugin