docstr: Returns True if the image has been built.
docstr_tok: ["Returns","True","if","the","image","has","been","built","."]
code: def is_built(self) -> bool:
      """Returns True if the image has been built."""
  
      return self.built_at is not None
  
file_path: PySyft/packages/syft/src/syft/service/worker/worker_image.py
imports: from typing import Optional
  from ...custom_worker.config import WorkerConfig
  from ...node.credentials import SyftVerifyKey
  from ...serde.serializable import serializable
  from ...types.datetime import DateTime
  from ...types.syft_object import SYFT_OBJECT_VERSION_1
  from ...types.syft_object import SyftObject
  from ...types.uid import UID
  from .image_identifier import SyftWorkerImageIdentifier
label_desc: Use image node_id 1 for calling the SyftWorkerImage obj's underlying member method code with example usage: obj.is_built() and returns: unknown