horizon层层注册

# horizon/base.py
# 定义Dashboard类、PanelGroup类和Panel类。
horizon = HorizonSite()

# project/dashboard.py
Class BasePanels(horizon.PanelGroup):
panels = (‘abc’,)# abc（Panel）注册在BasePanels（PanelGroup）
Class Project(horizon.Dashboard):
panels=(BasePanels,)# BasePanels注册在project
horizon.register(Project)# project（Dashboard）注册在全局horizon实例

# project/abc/panel.py
class Abc(horizon.Panel):
slug = "abc"
dashboard.Project.register(Abc)# 将Abc（Panel）实例注册在project（Dashboard）