code: def validation(args):
      checkpoint = Checkpoint(
          rank=0,
          world_size=1,
          embedding_size=args.embedding_size,
          num_classes=None,
          checkpoint_dir=args.checkpoint_dir,
      )
  
      backbone = eval("backbones.{}".format(args.backbone))(
          num_features=args.embedding_size
      )
      checkpoint.load(backbone, for_train=False, dtype="float32")
      backbone.eval()
  
      callback_verification = CallBackVerification(
          1, 0, args.batch_size, args.val_targets, args.data_dir
      )
  
      callback_verification(1, backbone)
  
imports: import os
  import numpy
  import paddle
  from .utils.verification import CallBackVerification
  from .utils.io import Checkpoint
  from .None import backbones
label_desc: Use image node_id 1 for calling a global function with example usage: validation(args) without return types