class_docstr: Simple dataclasses.
  
  These are intended to be used for actual data, such as returned by
  dataset.examples and model.predict().
  
  Contrast with LitType and descendants, which are used in model and dataset
  /specs/ to represent types and metadata.
class_docstr_tok: ["Simple","dataclasses",".","These","are","intended","to","be","used","for","actual","data",",","such","as","returned","by","dataset.examples","and","model.predict","(",")",".","Contrast","with","LitType","and","descendants",",","which","are","used","in","model","and","dataset","\/specs\/","to","represent","types","and","metadata","."]
docstr: Used by serialize.py.
docstr_tok: ["Used","by","serialize.py","."]
code: def to_json(self) -> JsonDict:
      """Used by serialize.py."""
      d = attr.asdict(self, recurse=False)
      d["__class__"] = "DataTuple"
      d["__name__"] = self.__class__.__name__
      return d
  
imports: import abc
  from collections.abc import Sequence
  from typing import Any, Optional, Union
  import attr
label_desc: Use image node_id 1 for calling the DataTuple obj's underlying member method code with example usage: obj.to_json() and returns: d