code: def to_json(
      self, run_or_artifact: Optional[Union["LocalRun", "Artifact"]]
  ) -> dict:
      json_obj = {}
      # This is a bit of a hack to allow _ClassesIdType to
      # be able to operate fully without an artifact in play.
      # In all other cases, artifact should be a true artifact.
      if run_or_artifact is not None:
          json_obj = super().to_json(run_or_artifact)
      json_obj["_type"] = Classes._log_type
      json_obj["class_set"] = self._class_set
      return json_obj
  
file_path: wandb/wandb/sdk/data_types/helper_types/classes.py
imports: import os
  from typing import TYPE_CHECKING, Any, Dict, Optional, Sequence, Type, Union
  from ..None import _dtypes
  from ..base_types.media import Media
label_desc: Use image node_id 3 for calling the Classes obj's underlying member method code with example usage: obj.to_json(run_or_artifact) and returns: json_obj