code: def _get_router_ids_from_removed_devices_info(removed_devices_info):
          
          removed_router_ids = []
          for hd_id, resources in removed_devices_info['hosting_data'].items():
              removed_router_ids += resources.get('routers', [])
          return removed_router_ids
docs: Extract router_ids from the removed devices info dict.
  
          :param removed_devices_info: Dict of removed devices and their
                 associated resources.
          Format:
                  {
                    'hosting_data': {'hd_id1': {'routers': [id1, id2, ...]},
                                     'hd_id2': {'routers': [id3, id4, ...]},
                                     ...
                                    },
                    'deconfigure': True/False
                  }
          :return removed_router_ids: List of removed router ids