code: def visualize(
      self, _attribution, _data, contribution_frac
  ) -> FeatureOutput:
      return FeatureOutput(
          name=self.name,
          base=None,
          modified=None,
          type=self.visualization_type(),
          contribution=contribution_frac,
      )
  
imports: import base64
  import warnings
  from collections import namedtuple
  from io import BytesIO
  from typing import Callable, List, Optional, Union
  from captum._utils.common import safe_div
  from captum.attr._utils import visualization
  from captum.insights.attr_vis._utils.transforms import format_transforms
label_desc: Use image node_id 3 for calling the EmptyFeature obj's underlying member method code with example usage: obj.visualize(_attribution, _data, contribution_frac) and returns: FeatureOutput