class_docstr: Image database.
class_docstr_tok: ["Image","database","."]
code: def roidb(self):
      # A roidb is a list of dictionaries, each with the following keys:
      #   boxes
      #   gt_overlaps
      #   gt_classes
      #   flipped
      if self._roidb is not None:
          return self._roidb
      self._roidb = self.roidb_handler()
      return self._roidb
  
imports: import os
  import os.path
  import PIL
  import numpy
  import scipy.sparse
  from builtins import range
  import sys
  from .utils.cython_bbox import bbox_overlaps
label_desc: Use image node_id 8 for calling the imdb obj's underlying member method code with example usage: obj.roidb() and returns: self, self