Warn or error when using unsupported Python version

[GregoryComer]

🚀 The feature, motivation and pitch

Lowering can fail in weird ways when using older, unsupported Python versions. We should warn or error out when importing the executorch Python package on an unsupported Python version.

See #2025 for an example of this.

Alternatives

No response

Additional context

No response

RFC (Optional)

No response

cc @larryliu0820 @lucylq @mergennachin @byjlw

[ahbpp]

Hi there,

I'm not sure, but if the Python version is unsupported, it may be better to exit with an error in setup.py similar to the PyTorch repo (See: https://github.com/pytorch/pytorch/blob/main/setup.py#L240 ).

Or, if you think that it is better to error when importing, it can be in __init__.py at the package's root

I’d be happy to help with this issue if that’s okay

[mergennachin]

@ahbpp - feel free to put up a PR, thank you

cc @dbort , @larryliu0820 , @jathu

[GregoryComer]

Thanks for taking a look at this. Doing it setup.py seems reasonable.

[ahbpp]

Sorry, it is actually already implemented in install_requirements.py.
if executorch works with python>=3.11, the issue is resolved

(executorch_39) alekseikarpov:executorch_fork/ (main✗) $ ./install_executorch.sh                                                                                                                           
ERROR: ExecuTorch does not support python version 3.9.21: must satisfy ">=3.10"
(executorch_39) alekseikarpov:executorch_fork/ (main✗) $ python --version                                                                                                                                  
Python 3.9.21

[GregoryComer]

@ahbpp Ah, that must have been added semi-recently. Sorry about that. Thanks for finding this. I will close this issue.