code: def generate_pos_array(tree_num, max_node_num):
      dtype = get_dtype(max_node_num)
      # return list as a column of dataframe
      return [np.zeros(tree_num, dtype=dtype)]
  
file_path: FATE/python/fate/ml/ensemble/algo/secureboost/common/predict.py
imports: import pandas
  import numpy
  from typing import List
  from fate.arch import Context
  from fate.arch.dataframe import DataFrame
  import copy
  from fate.ml.ensemble.learner.decision_tree.tree_core.decision_tree import DecisionTree, _make_decision, Node
  import functools
  from logging import getLogger
label_desc: Use image node_id 4 for calling a global function with example usage: generate_pos_array(tree_num, max_node_num) and returns: list