code: def _new_chunks(self, inputs, kws=None, **kw):
      if "_key" in kw and self.source_key is None:
          self.source_key = kw["_key"]
      return super()._new_chunks(inputs, kws=kws, **kw)
  
imports: from ...serialization.serializables import BoolField
  from ..entity import OutputType, register_fetch_class
  from .base import Operand
  from .core import TileableOperandMixin
  from .fetch import FetchMixin, Fetch
  from .fuse import Fuse, FuseChunkMixin
label_desc: Use image node_id 2 for calling the ObjectFetch obj's underlying member method code with example usage: obj._new_chunks(inputs, kws) and returns: super