template tag for django-cms menus that roots at a given menu level

custom_nav_tags.py

from menus.menu_pool import menu_pool
from django import template
from menus.templatetags.menu_tags import cut_after

register = template.Library()

@register.inclusion_tag('cms/dummy.html', takes_context=True)
def show_rooted_sub_menu(context, levels=100, root_level=0, template="menu/sub_menu.html"):
   """
   show the sub menu of the current nav-node.
   -levels: how many levels deep
   -temlplate: template used to render the navigation
   """

   try:
       # If there's an exception (500), default context_processors may not be called.
       request = context['request']
   except KeyError:
       return {'template': 'menu/empty.html'}
   nodes = menu_pool.get_nodes(request)
   children = []
   for node in nodes:
       if (node.ancestor and node.level == root_level) or (node.selected and node.level == root_level):
           cut_after(node, levels, [])
           children = node.children
           for child in children:
               child.parent = None
           children = menu_pool.apply_modifiers(children, request, post_cut=True)
   context.update({'children':children,
                   'template':template,
                   'from_level':0,
                   'to_level':0,
                   'extra_inactive':0,
                   'extra_active':0
                   })
   return context