code: def shrink(self, bboxes, rate, max_shr=20):
      check_install("Polygon", "Polygon3")
      import Polygon as plg
  
      rate = rate * rate
      shrinked_bboxes = []
      for bbox in bboxes:
          area = plg.Polygon(bbox).area()
          peri = self.perimeter(bbox)
  
          try:
              pco = pyclipper.PyclipperOffset()
              pco.AddPath(
                  bbox, pyclipper.JT_ROUND, pyclipper.ET_CLOSEDPOLYGON
              )
              offset = min(
                  int(area * (1 - rate) / (peri + 0.001) + 0.5), max_shr
              )
  
              shrinked_bbox = pco.Execute(-offset)
              if len(shrinked_bbox) == 0:
                  shrinked_bboxes.append(bbox)
                  continue
  
              shrinked_bbox = np.array(shrinked_bbox[0])
              if shrinked_bbox.shape[0] <= 2:
                  shrinked_bboxes.append(bbox)
                  continue
  
              shrinked_bboxes.append(shrinked_bbox)
          except Exception as e:
              shrinked_bboxes.append(bbox)
  
      return shrinked_bboxes
  
imports: import os
  import cv2
  import random
  import pyclipper
  import paddle
  import numpy
  from ppocr.utils.utility import check_install
  import scipy.io
  from PIL import Image
  import paddle.vision.transforms
label_desc: Use image node_id 4 for calling the MakeShrink obj's underlying member method code with example usage: obj.shrink(bboxes, rate, max_shr) and returns: shrinked_bboxes