class_docstr: Randomly crop images and make sure to contain at least one intact
  instance.
code: def __repr__(self):
      repr_str = self.__class__.__name__
      return repr_str
  
imports: import numpy
  from PIL import Image, ImageDraw
  import cv2
  from shapely.geometry import Polygon
  import math
  from ppocr.utils.poly_nms import poly_intersection
label_desc: Use image node_id 6 for calling the RandomCropPolyInstances obj's underlying member method code with example usage: obj.__repr__() and returns: repr_str