Django如何将自定义变量传递给上下文以在自定义管理模板中使用？

Django如何将自定义变量传递给上下文以在自定义管理模板中使用？

class MyModelAdmin(admin.ModelAdmin):    ...    def changelist_view(self, request, extra_context=None):        extra_context = extra_context or {}        extra_context['some_var'] = 'This is what I want to show'        return super(MyModelAdmin, self).changelist_view(request, extra_context=extra_context)