code: def __repr__(self):
      if self.op.stage is None:
          return (
              f"{type(self).__name__} <op={type(self.op).__name__}, "
              f"key={self.key}>"
          )
      else:
          return (
              f"{type(self).__name__} <op={type(self.op).__name__}, "
              f"stage={self.op.stage.name}, key={self.key}>"
          )
  
file_path: mars/mars/core/entity/chunks.py
imports: from ...serialization.serializables import BoolField, FieldTypes, TupleField
  from ...utils import tokenize
  from .core import EntityData, Entity
label_desc: Use image node_id 1 for calling the ChunkData obj's underlying member method code with example usage: obj.__repr__() and returns: type, str, type, str, self, str, type, str, type, str, self, str, self, str