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<@ULVA73B9P> why am I getting TypeError: ‘NoneType’ object is not iterable when using the command `prefect deployment run`

It appears that the error you're encountering with the `prefect deployment run` command is likely due to an issue with a dependency called `typer`. The relevant issue has been documented <https://github.com/PrefectHQ/prefect/issues/12397|here on GitHub>.

Here's a brief summary:

- **Issue**: Some CLI commands, including `prefect deployment run`, are broken due to changes in `typer` version `0.10.0`. This can cause commands to receive `None` instead of an expected list, leading to the `TypeError: 'NoneType' object is not iterable` error.
- **Cause**: `typer` released a new version changing the default behavior which Prefect's CLI wasn't expecting.
- **Solution**: Downgrading `typer` to a version below `0.10.0` should resolve the issue.

```bash
pip install typer&lt;0.10.0
```

Alternatively, you may want to keep an eye on the issue for any updates or fixes provided by the Prefect team.

hi <@U04GGMY0G68> - you should also be able to upgrade prefect instead of downgrading `typer`, since we have handled this in new versions of prefect

Good to know <@U02GMEZU18B>! ty for the suggestion