code: def build_slot_holder(discrete_slot_names):
      """build discrete slot holders"""
      holder_list = []
      discrete_slot_holders = []
      discrete_slot_lod_holders = []
      for slot in discrete_slot_names:
          holder = static.data(
              slot, shape=[None, 1], dtype="int64", lod_level=1
          )
          discrete_slot_holders.append(holder)
          holder_list.append(holder)
  
          lod_holder = static.data(
              "slot_%s_lod" % slot,
              shape=[None],
              dtype="int64",
              lod_level=0,
          )
          discrete_slot_lod_holders.append(lod_holder)
          holder_list.append(lod_holder)
  
      return (
          discrete_slot_holders,
          discrete_slot_lod_holders,
          holder_list,
      )
  
imports: import os
  import sys
  import math
  import time
  import numpy
  import pickle
  import paddle
  import paddle.fluid
  import paddle.fluid.layers
  import paddle.static
  from paddle.common_ops_import import LayerHelper, check_type, check_variable_and_dtype
  from paddle.fluid.framework import Variable
  import pgl
  from pgl.utils.logger import log
label_desc: Use image node_id 7 for calling a global function with example usage: build_slot_holder(discrete_slot_names) and returns: discrete_slot_holders,  discrete_slot_lod_holders,  holder_list