'Unregisters a :class:`~horizon.Panel` from this dashboard.'

@classmethod
def unregister(cls, panel):

    success = Horizon.unregister_panel(cls, panel)
    if success:
        key = os.path.join(cls.slug, panel.slug)
        if (key in loaders.panel_template_dirs):
            del loaders.panel_template_dirs[key]
    return success
