code: def mean_iou(true_boxes, predicted_boxes):
      if len(true_boxes) != len(predicted_boxes):
          raise ValueError("Array size mismatch")
  
      all_iou = [
          bounding_box_iou(y_true, y_pred)
          for y_true, y_pred in zip(true_boxes, predicted_boxes)
      ]
  
      return np.mean(all_iou)
  
imports: import functools
  import numpy
  import sklearn.metrics
  from fairlearn.metrics import MetricFrame
label_desc: Use image node_id 2 for calling a global function with example usage: mean_iou(true_boxes, predicted_boxes) and returns: np