_TYPER_STANDARD_TRACEBACK env is not compatible with AWS Lambda

[colin-nolan]

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Example Code

n/a

Description

Typer allows pretty exceptions can be disabled using the _TYPER_STANDARD_TRACEBACK environment variable:
https://typer.tiangolo.com/tutorial/exceptions/#disable-pretty-exceptions (which is super useful).

However, due to the underscore at the start of the variable, it can't be used in AWS Lambda:

I would like to suggest the solution of a none underscore-prefixed version is supported (in addition).

I'd be happy to put a PR in for this - I wanted to check it would be supported first, as I am not aware as to why the variable takes this non-standard name (perhaps it's intended to indicate that it's a "private" environment variable - that's advertised publically in the docs?).

Operating System

Other

Operating System Details

No response

Typer Version

master

Python Version

3.13

Additional Context

No response

[svlandeg]

Hm, you're right that it seems a bit odd to be a publicly advertised var that starts with an underscore. A PR hopefully shouldn't be too much work, but we do need to make sure we continue to support the original env var for backwards compatibility. If you're up for creating the PR, feel free to ping me, then I'll review and run it by Tiangolo. Thanks! 🙏

[colin-nolan]

Thanks. I'll add a PR within the next few days.