Exception type: UnexpectedResponseError
Message: Server returned unexpected status code: 502 (https://debusine.trinitydesktop.net/api/1.0/artifact/trinity-testing/27521/)

Traceback (most recent call last):
  File "/usr/lib/python3/dist-packages/debusine/tasks/_task.py", line 849, in _execute
    if not self.configure_for_execution(download_directory):
           ~~~~~~~~~~~~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3/dist-packages/debusine/tasks/blhc.py", line 133, in configure_for_execution
    self._prepare_executor_instance()
    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^^
  File "/usr/lib/python3/dist-packages/debusine/tasks/_task.py", line 980, in _prepare_executor_instance
    self._prepare_executor()
    ~~~~~~~~~~~~~~~~~~~~~~^^
  File "/usr/lib/python3/dist-packages/debusine/tasks/_task.py", line 963, in _prepare_executor
    self.executor = executor_class(self.backend)(
                    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~^
        self.debusine,
        ^^^^^^^^^^^^^^
        self.dynamic_data.environment_id,
        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
        workspace=self.workspace_name,
        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    )
    ^
  File "/usr/lib/python3/dist-packages/debusine/tasks/executors/unshare.py", line 60, in __init__
    self.system_image = self._image_cache.image_artifact(system_image_id)
                        ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3/dist-packages/debusine/tasks/executors/images.py", line 82, in image_artifact
    r = self.debusine_api.artifact_get(
        artifact_id, workspace=self.workspace
    )
  File "/usr/lib/python3/dist-packages/debusine/client/debusine.py", line 416, in artifact_get
    return self._debusine_http_client.get(path, ArtifactResponse)
           ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3/dist-packages/debusine/client/debusine_http_client.py", line 41, in get
    return self._api_request("GET", self._api_url + path, expected_class)
           ~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3/dist-packages/debusine/client/debusine_http_client.py", line 319, in _api_request
    raise exceptions.UnexpectedResponseError(
    ...<2 lines>...
    )
debusine.client.exceptions.UnexpectedResponseError: Server returned unexpected status code: 502 (https://debusine.trinitydesktop.net/api/1.0/artifact/trinity-testing/27521/)