code: def test_default_callable(self):
      @handle_legacy_interface(
          weights=(
              "pretrained",
              lambda kwargs: self.ModelWeights.Sentinel
              if kwargs["flag"]
              else None,
          )
      )
      def builder(*, weights=None, flag):
          pass
  
      with pytest.warns(UserWarning, match="deprecated"):
          builder(pretrained=True, flag=True)
  
      with pytest.raises(ValueError, match="weights"):
          builder(pretrained=True, flag=False)
  
imports: import copy
  import os
  import pickle
  import pytest
  import test_models
  import torch
  from common_extended_utils import get_file_size_mb, get_ops
  from torchvision import models
  from torchvision.models import get_model_weights, Weights, WeightsEnum
  from torchvision.models._utils import handle_legacy_interface
  from torchvision.models.detection.backbone_utils import mobilenet_backbone, resnet_fpn_backbone
label_desc: Use image node_id 6 for calling the TestHandleLegacyInterface obj's underlying member method code with example usage: obj.test_default_callable() without return types