code: def bbox_area(src_bbox):
      if src_bbox[2] < src_bbox[0] or src_bbox[3] < src_bbox[1]:
          return 0.0
      else:
          width = src_bbox[2] - src_bbox[0]
          height = src_bbox[3] - src_bbox[1]
          return width * height
  
imports: from __future__ import absolute_import
  from __future__ import division
  from __future__ import print_function
  import numpy
  import random
  import math
  import cv2
label_desc: Use image node_id 3 for calling a global function with example usage: bbox_area(src_bbox) and returns: int, unknown