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Another orion question, im now playing with deployments but the runs dont seem to be executing correctly.  I’m seeing
```08:01:52.893 | Submitting flow run 'f37fba9f-4280-431d-9f43-889e53192f24'
08:01:52.894 | Completed submission of flow run 'f37fba9f-4280-431d-9f43-889e53192f24'
08:01:52.901 | Finished monitoring for late runs.
08:01:54.187 | Flow run 'f37fba9f-4280-431d-9f43-889e53192f24' exited with exception: KeyError('__main__')```

my deployment:
```from prefect.deployments import DeploymentSpec
from prefect.orion.schemas.schedules import IntervalSchedule
from datetime import timedelta


# note that deployment names are 
# stored and referenced as '&lt;flow name&gt;/&lt;deployment name&gt;'
DeploymentSpec(
    flow_location="/Users/lawrencefinn/orion_example_flow.py",
    name="my-first-deployment",
    parameters={"nums": [1, 2, 3, 4]}, 
    schedule=IntervalSchedule(interval=timedelta(minutes=1)),
)```


my flow:
```from prefect import flow, task
from prefect.executors import DaskExecutor, SequentialExecutor

@task
def say_it(stuff):
    print(f"Saying {stuff}")

@flow(executor=DaskExecutor(cluster_kwargs={"n_workers": 4, "threads_per_worker": 1}))
def my_favorite_function():
    say_it("hello")
    return 0

# if __name__ == "__main__":
#     my_favorite_function()```

I also see things like
```08:06:53.106 | Completed submission of flow run 'bb8c741e-da03-4746-9b7b-57970c425745'
Exception in callback SubprocessStreamProtocol.pipe_data_received(1, b"EXCEPTION 8...XCEPTION 81\n")
handle: &lt;Handle SubprocessStreamProtocol.pipe_data_received(1, b"EXCEPTION 8...XCEPTION 81\n")&gt;
Traceback (most recent call last):
  File "/Users/lawrencefinn/.pyenv/versions/3.8.5/lib/python3.8/asyncio/events.py", line 81, in _run
    self._context.run(self._callback, *self._args)
  File "/Users/lawrencefinn/.pyenv/versions/3.8.5/lib/python3.8/asyncio/subprocess.py", line 73, in pipe_data_received
    reader.feed_data(data)
  File "/Users/lawrencefinn/.pyenv/versions/3.8.5/lib/python3.8/asyncio/streams.py", line 472, in feed_data
    assert not self._eof, 'feed_data after feed_eof'
AssertionError: feed_data after feed_eof```

I tried to reproduce - using the same flow file you shared, I also got KeyError(’__main__‘) when a flow is scheduled and it uses Dask executor. I tried it with both, once with and once without main:
```if __name__ == "__main__":
    my_favorite_function()```
But when removing the executor, it works fine with the deployment.

Btw. your flow doesn’t have a flow name on the @flow decorator and your deployment specifies parameters that you don’t use in your flow - this shouldn’t be the problem here, but just to let you know.

Thanks for checking and reporting that.

Agents still exist in Orion, but they are no longer required to run your flows. Agents will only be required for automatically scheduled/API-triggered deployment runs.

This will work if you disable subprocesses for the dask workers `DaskExecutor(cluster_kwargs=dict(processes=False))` -- well investigate a fix though!