code: def get_gt_boxes(gt_dir):
      """gt dir: (wider_face_val.mat, wider_easy_val.mat, wider_medium_val.mat, wider_hard_val.mat)"""
  
      gt_mat = loadmat(os.path.join(gt_dir, "wider_face_val.mat"))
      hard_mat = loadmat(os.path.join(gt_dir, "wider_hard_val.mat"))
      medium_mat = loadmat(os.path.join(gt_dir, "wider_medium_val.mat"))
      easy_mat = loadmat(os.path.join(gt_dir, "wider_easy_val.mat"))
  
      facebox_list = gt_mat["face_bbx_list"]
      event_list = gt_mat["event_list"]
      file_list = gt_mat["file_list"]
  
      hard_gt_list = hard_mat["gt_list"]
      medium_gt_list = medium_mat["gt_list"]
      easy_gt_list = easy_mat["gt_list"]
  
      return (
          facebox_list,
          event_list,
          file_list,
          hard_gt_list,
          medium_gt_list,
          easy_gt_list,
      )
  
imports: from __future__ import absolute_import
  import os
  import tqdm
  import pickle
  import datetime
  import argparse
  import numpy
  from scipy.io import loadmat
label_desc: Use image node_id 6 for calling a global function with example usage: get_gt_boxes(gt_dir) and returns: facebox_list,  event_list,  file_list,  hard_gt_list,  medium_gt_list,  easy_gt_list