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Hi again everyone, I am trying to replicate the [D...
# ask-community
m
Hi again everyone, I am trying to replicate the [Dask Cluster on Kubernetes deployment recipe](https://docs.prefect.io/orchestration/recipes/k8s_dask.html) and I face the following error
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AttributeError: 'FunctionTask' object has no attribute 'result'
Wondering if you have encountered this before - One thing to note is if the flow is empty then it runs successfully … I am using prefect version 
0.10.7
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19 May 2020,07:027 	agent	INFO	Submitted for execution: Job prefect-job-d3fc6dc5
19 May 2020,07:02:12 	prefect.CloudFlowRunner	INFO	Beginning Flow run for 'Static Dask Cluster'
19 May 2020,07:02:12 	prefect.CloudFlowRunner	INFO	Starting flow run.
19 May 2020,07:02:12 	prefect.CloudFlowRunner	DEBUG	Flow 'Static Dask Cluster': Handling state change from Scheduled to Running
19 May 2020,07:02:12 	prefect.CloudFlowRunner	ERROR	Unexpected error: AttributeError("'FunctionTask' object has no attribute 'result'")
Traceback (most recent call last):
  File "/usr/local/lib/python3.7/site-packages/prefect/engine/runner.py", line 48, in inner
    new_state = method(self, state, *args, **kwargs)
  File "/usr/local/lib/python3.7/site-packages/prefect/engine/flow_runner.py", line 465, in get_flow_run_state
    for t in final_tasks
  File "/usr/local/lib/python3.7/site-packages/prefect/engine/executors/dask.py", line 196, in wait
    return self.client.gather(futures)
  File "/usr/local/lib/python3.7/site-packages/distributed/client.py", line 1931, in gather
    asynchronous=asynchronous,
  File "/usr/local/lib/python3.7/site-packages/distributed/client.py", line 780, in sync
    self.loop, func, *args, callback_timeout=callback_timeout, **kwargs
  File "/usr/local/lib/python3.7/site-packages/distributed/utils.py", line 347, in sync
    raise exc.with_traceback(tb)
  File "/usr/local/lib/python3.7/site-packages/distributed/utils.py", line 331, in f
    result[0] = yield future
  File "/usr/local/lib/python3.7/site-packages/tornado/gen.py", line 735, in run
    value = future.result()
  File "/usr/local/lib/python3.7/site-packages/distributed/client.py", line 1790, in _gather
    raise exception.with_traceback(traceback)
  File "/usr/local/lib/python3.7/site-packages/prefect/engine/flow_runner.py", line 569, in run_task
    default_handler = task.result_handler or self.flow.result_handler
AttributeError: 'FunctionTask' object has no attribute 'result'
19 May 2020,07:02:12 	prefect.CloudFlowRunner	DEBUG	Flow 'Static Dask Cluster': Handling state change from Running to Failed
c
Hi @Marwan Sarieddine - this is a symptom of your dask workers running an older version of Prefect (pre 0.11.0)
m
@Chris White - thank you for your response - yep just updated the images to use 0.11.1 and it runs fine now
💯 1
As a follow up - I guess ideally I would want to try the dask-kubernetes approach of dynamically provisioning worker pods opposed to the static dask cluster implementation I mention above - so I tried to replicate the example on [Dask Kubernetes Environment](https://docs.prefect.io/orchestration/execution/dask_k8s_environment.html#overview) and I am getting this 
ast.literal_eval
error with the logs: I am using prefect version 
0.11.1
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$ kubectl logs prefect-dask-job-6490fd77-df9b-4c03-9e05-0e5f64ea86ee-9czqp 
Traceback (most recent call last):
  File "<string>", line 1, in <module>
  File "/usr/local/lib/python3.7/site-packages/prefect/__init__.py", line 1, in <module>
    import prefect.utilities
  File "/usr/local/lib/python3.7/site-packages/prefect/utilities/__init__.py", line 1, in <module>
    import prefect.utilities.logging
  File "/usr/local/lib/python3.7/site-packages/prefect/utilities/logging.py", line 252, in <module>
    configure_extra_loggers()
  File "/usr/local/lib/python3.7/site-packages/prefect/utilities/logging.py", line 247, in configure_extra_loggers
    loggers = literal_eval(context.config.logging.get("extra_loggers", "[]"))
  File "/usr/local/lib/python3.7/ast.py", line 91, in literal_eval
    return _convert(node_or_string)
  File "/usr/local/lib/python3.7/ast.py", line 90, in _convert
    return _convert_signed_num(node)
  File "/usr/local/lib/python3.7/ast.py", line 63, in _convert_signed_num
    return _convert_num(node)
  File "/usr/local/lib/python3.7/ast.py", line 55, in _convert_num
    raise ValueError('malformed node or string: ' + repr(node))
ValueError: malformed node or string: <BoxList: ['dask_kubernetes.core', 'distributed.deploy.adaptive', 'kubernetes']>
not quite sure why that is the case … seems like there is an attempt to extend the prefect loggers that fails …
c
Apologies for that issue - if you upgrade to 0.11.2 it should be resolved
m
@Chris White - yep upgrading to 0.11.2 solves the problem - thanks
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