class_docstr: 将DefaultBox与GT进行匹配
class_docstr_tok: ["\u5c06DefaultBox\u4e0eGT\u8fdb\u884c\u5339\u914d"]
code: def __call__(self, image, target):
      boxes = target["boxes"]
      labels = target["labels"]
      # bboxes_out (Tensor 8732 x 4), labels_out (Tensor 8732)
      bboxes_out, labels_out = self.encoder.encode(boxes, labels)
      target["boxes"] = bboxes_out
      target["labels"] = labels_out
  
      return image, target
  
imports: import random
  import torch
  import torchvision.transforms
  from torchvision.transforms import functional
  from src import dboxes300_coco, calc_iou_tensor, Encoder
label_desc: Use image node_id 2 for calling the AssignGTtoDefaultBox obj's underlying member method code with example usage: obj.__call__(image, target) and returns: image,  target